diff --git a/mock_update_attempter.h b/mock_update_attempter.h
index d502222..96d93fd 100644
--- a/mock_update_attempter.h
+++ b/mock_update_attempter.h
@@ -32,17 +32,7 @@
 
   MOCK_METHOD(void,
               Update,
-              (const std::string& app_version,
-               const std::string& omaha_url,
-               const std::string& target_channel,
-               const std::string& lts_tag,
-               const std::string& target_version_prefix,
-               bool rollback_allowed,
-               bool rollback_data_save_requested,
-               int rollback_allowed_milestones,
-               bool rollback_on_channel_downgrade,
-               bool obey_proxies,
-               bool interactive),
+              (const chromeos_update_manager::UpdateCheckParams& params),
               (override));
 
   MOCK_METHOD1(GetStatus, bool(update_engine::UpdateEngineStatus* out_status));
diff --git a/omaha_request_params.cc b/omaha_request_params.cc
index 8a2e3dc..79d19e8 100644
--- a/omaha_request_params.cc
+++ b/omaha_request_params.cc
@@ -37,9 +37,11 @@
 #include "update_engine/common/platform_constants.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/system_state.h"
+#include "update_engine/update_manager/policy.h"
 
 #define CALL_MEMBER_FN(object, member) ((object).*(member))
 
+using chromeos_update_manager::UpdateCheckParams;
 using std::string;
 
 namespace chromeos_update_engine {
@@ -59,9 +61,9 @@
     test::SetImagePropertiesRootPrefix(nullptr);
 }
 
-bool OmahaRequestParams::Init(const string& in_app_version,
-                              const string& in_update_url,
-                              bool in_interactive) {
+bool OmahaRequestParams::Init(const string& app_version,
+                              const string& update_url,
+                              const UpdateCheckParams& params) {
   LOG(INFO) << "Initializing parameters for this update attempt";
   image_props_ = LoadImageProperties(system_state_);
   mutable_image_props_ = LoadMutableImageProperties(system_state_);
@@ -77,15 +79,15 @@
 
   os_platform_ = constants::kOmahaPlatformName;
   if (!image_props_.system_version.empty()) {
-    if (in_app_version == "ForcedUpdate") {
-      image_props_.system_version = in_app_version;
+    if (app_version == "ForcedUpdate") {
+      image_props_.system_version = app_version;
     }
     os_version_ = image_props_.system_version;
   } else {
     os_version_ = OmahaRequestParams::kOsVersion;
   }
-  if (!in_app_version.empty())
-    image_props_.version = in_app_version;
+  if (!app_version.empty())
+    image_props_.version = app_version;
 
   os_sp_ = image_props_.version + "_" + GetMachineType();
   app_lang_ = "en-US";
@@ -115,17 +117,51 @@
     delta_okay_ = false;
   }
 
-  if (in_update_url.empty())
+  if (update_url.empty())
     update_url_ = image_props_.omaha_url;
   else
-    update_url_ = in_update_url;
+    update_url_ = update_url;
 
   // Set the interactive flag accordingly.
-  interactive_ = in_interactive;
+  interactive_ = params.interactive;
 
   dlc_apps_params_.clear();
   // Set false so it will do update by default.
   is_install_ = false;
+
+  target_version_prefix_ = params.target_version_prefix;
+
+  lts_tag_ = params.lts_tag;
+
+  rollback_allowed_ = params.rollback_allowed;
+
+  // Set whether saving data over rollback is requested.
+  rollback_data_save_requested_ = params.rollback_data_save_requested;
+
+  // Set how many milestones of rollback are allowed.
+  rollback_allowed_milestones_ = params.rollback_allowed_milestones;
+
+  // Set the target channel, if one was provided.
+  if (params.target_channel.empty()) {
+    LOG(INFO) << "No target channel mandated by policy.";
+  } else {
+    LOG(INFO) << "Setting target channel as mandated: "
+              << params.target_channel;
+    string error_message;
+    if (!SetTargetChannel(params.target_channel,
+                          params.rollback_on_channel_downgrade,
+                          &error_message)) {
+      LOG(ERROR) << "Setting the channel failed: " << error_message;
+    }
+
+    // Since this is the beginning of a new attempt, update the download
+    // channel. The download channel won't be updated until the next attempt,
+    // even if target channel changes meanwhile, so that how we'll know if we
+    // should cancel the current download attempt if there's such a change in
+    // target channel.
+    UpdateDownloadChannel();
+  }
+
   return true;
 }
 
diff --git a/omaha_request_params.h b/omaha_request_params.h
index 1e9ab7d..7e19262 100644
--- a/omaha_request_params.h
+++ b/omaha_request_params.h
@@ -30,6 +30,7 @@
 #include "update_engine/common/constants.h"
 #include "update_engine/common/platform_constants.h"
 #include "update_engine/image_properties.h"
+#include "update_engine/update_manager/policy.h"
 
 // This gathers local system information and prepares info used by the
 // Omaha request action.
@@ -249,7 +250,7 @@
   // of the parameter. Returns true on success, false otherwise.
   bool Init(const std::string& in_app_version,
             const std::string& in_update_url,
-            bool in_interactive);
+            const chromeos_update_manager::UpdateCheckParams& params);
 
   // Permanently changes the release channel to |channel|. Performs a
   // powerwash, if required and allowed.
diff --git a/omaha_request_params_unittest.cc b/omaha_request_params_unittest.cc
index 110fb2b..140cad3 100644
--- a/omaha_request_params_unittest.cc
+++ b/omaha_request_params_unittest.cc
@@ -75,36 +75,36 @@
 }  // namespace
 
 TEST_F(OmahaRequestParamsTest, MissingChannelTest) {
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   // By default, if no channel is set, we should track the stable-channel.
   EXPECT_EQ("stable-channel", params_.target_channel());
 }
 
 TEST_F(OmahaRequestParamsTest, ForceVersionTest) {
-  EXPECT_TRUE(params_.Init("ForcedVersion", "", false));
+  EXPECT_TRUE(params_.Init("ForcedVersion", "", {}));
   EXPECT_EQ(string("ForcedVersion_") + GetMachineType(), params_.os_sp());
   EXPECT_EQ("ForcedVersion", params_.app_version());
 }
 
 TEST_F(OmahaRequestParamsTest, ForcedURLTest) {
-  EXPECT_TRUE(params_.Init("", "http://forced.google.com", false));
+  EXPECT_TRUE(params_.Init("", "http://forced.google.com", {}));
   EXPECT_EQ("http://forced.google.com", params_.update_url());
 }
 
 TEST_F(OmahaRequestParamsTest, MissingURLTest) {
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   EXPECT_EQ(constants::kOmahaDefaultProductionURL, params_.update_url());
 }
 
 TEST_F(OmahaRequestParamsTest, DeltaOKTest) {
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   EXPECT_TRUE(params_.delta_okay());
 }
 
 TEST_F(OmahaRequestParamsTest, NoDeltasTest) {
   ASSERT_TRUE(
       WriteFileString(tempdir_.GetPath().Append(".nodelta").value(), ""));
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   EXPECT_FALSE(params_.delta_okay());
 }
 
@@ -112,12 +112,12 @@
   {
     OmahaRequestParams params(&fake_system_state_);
     params.set_root(tempdir_.GetPath().value());
-    EXPECT_TRUE(params.Init("", "", false));
+    EXPECT_TRUE(params.Init("", "", {}));
     EXPECT_TRUE(params.SetTargetChannel("canary-channel", false, nullptr));
     EXPECT_FALSE(params.mutable_image_props_.is_powerwash_allowed);
   }
   params_.set_root(tempdir_.GetPath().value());
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   EXPECT_EQ("canary-channel", params_.target_channel());
   EXPECT_FALSE(params_.mutable_image_props_.is_powerwash_allowed);
 }
@@ -126,12 +126,12 @@
   {
     OmahaRequestParams params(&fake_system_state_);
     params.set_root(tempdir_.GetPath().value());
-    EXPECT_TRUE(params.Init("", "", false));
+    EXPECT_TRUE(params.Init("", "", {}));
     EXPECT_TRUE(params.SetTargetChannel("canary-channel", true, nullptr));
     EXPECT_TRUE(params.mutable_image_props_.is_powerwash_allowed);
   }
   params_.set_root(tempdir_.GetPath().value());
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   EXPECT_EQ("canary-channel", params_.target_channel());
   EXPECT_TRUE(params_.mutable_image_props_.is_powerwash_allowed);
 }
@@ -141,7 +141,7 @@
     OmahaRequestParams params(&fake_system_state_);
     params.set_root(tempdir_.GetPath().value());
     SetLockDown(true);
-    EXPECT_TRUE(params.Init("", "", false));
+    EXPECT_TRUE(params.Init("", "", {}));
     params.image_props_.allow_arbitrary_channels = false;
     string error_message;
     EXPECT_FALSE(
@@ -151,7 +151,7 @@
     EXPECT_FALSE(params.mutable_image_props_.is_powerwash_allowed);
   }
   params_.set_root(tempdir_.GetPath().value());
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   EXPECT_EQ("stable-channel", params_.target_channel());
   EXPECT_FALSE(params_.mutable_image_props_.is_powerwash_allowed);
 }
@@ -197,7 +197,7 @@
 
   // When set to a valid value while a change is already pending, it should
   // succeed.
-  params_.Init("", "", false);
+  params_.Init("", "", {});
   EXPECT_TRUE(params_.SetTargetChannel("beta-channel", true, nullptr));
   // The target channel should reflect the change, but the download channel
   // should continue to retain the old value ...
@@ -237,7 +237,7 @@
 }
 
 TEST_F(OmahaRequestParamsTest, TargetChannelHintTest) {
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   const string kHint("foo-hint");
   params_.set_lts_tag(kHint);
   EXPECT_EQ(kHint, params_.lts_tag());
@@ -266,7 +266,7 @@
 }
 
 TEST_F(OmahaRequestParamsTest, RequisitionIsSetTest) {
-  EXPECT_TRUE(params_.Init("", "", false));
+  EXPECT_TRUE(params_.Init("", "", {}));
   EXPECT_EQ("fake_requisition", params_.device_requisition());
 }
 }  // namespace chromeos_update_engine
diff --git a/payload_state_unittest.cc b/payload_state_unittest.cc
index 8667548..2d571c1 100644
--- a/payload_state_unittest.cc
+++ b/payload_state_unittest.cc
@@ -630,7 +630,7 @@
   PayloadState payload_state;
   FakeSystemState fake_system_state;
   OmahaRequestParams params(&fake_system_state);
-  params.Init("", "", true);  // interactive = True.
+  params.Init("", "", {.interactive = true});
   fake_system_state.set_request_params(&params);
 
   EXPECT_TRUE(payload_state.Initialize(&fake_system_state));
@@ -653,7 +653,7 @@
   PayloadState payload_state;
   FakeSystemState fake_system_state;
   OmahaRequestParams params(&fake_system_state);
-  params.Init("", "", false);  // interactive = False.
+  params.Init("", "", {});
   fake_system_state.set_request_params(&params);
 
   EXPECT_TRUE(payload_state.Initialize(&fake_system_state));
@@ -1019,7 +1019,7 @@
   // Mock out the os version and make sure it's excluded correctly.
   string rollback_version = "2345.0.0";
   OmahaRequestParams params(&fake_system_state);
-  params.Init(rollback_version, "", false);
+  params.Init(rollback_version, "", {});
   fake_system_state.set_request_params(&params);
 
   EXPECT_TRUE(payload_state.Initialize(&fake_system_state));
diff --git a/real_system_state.cc b/real_system_state.cc
index 74a37f3..924271e 100644
--- a/real_system_state.cc
+++ b/real_system_state.cc
@@ -138,7 +138,7 @@
   // will be re-initialized before every request using the actual request
   // options. This initialization here pre-loads current channel and version, so
   // the DBus service can access it.
-  if (!request_params_.Init("", "", false)) {
+  if (!request_params_.Init("", "", {})) {
     LOG(WARNING) << "Ignoring OmahaRequestParams initialization error. Some "
                     "features might not work properly.";
   }
diff --git a/update_attempter.cc b/update_attempter.cc
index 14d5837..38b0f82 100644
--- a/update_attempter.cc
+++ b/update_attempter.cc
@@ -244,17 +244,7 @@
   system_state_->metrics_reporter()->ReportDailyMetrics(age);
 }
 
-void UpdateAttempter::Update(const string& app_version,
-                             const string& omaha_url,
-                             const string& target_channel,
-                             const string& lts_tag,
-                             const string& target_version_prefix,
-                             bool rollback_allowed,
-                             bool rollback_data_save_requested,
-                             int rollback_allowed_milestones,
-                             bool rollback_on_channel_downgrade,
-                             bool obey_proxies,
-                             bool interactive) {
+void UpdateAttempter::Update(const UpdateCheckParams& params) {
   // This is normally called frequently enough so it's appropriate to use as a
   // hook for reporting daily metrics.
   // TODO(garnold) This should be hooked to a separate (reliable and consistent)
@@ -283,21 +273,11 @@
     return;
   }
 
-  if (!CalculateUpdateParams(app_version,
-                             omaha_url,
-                             target_channel,
-                             lts_tag,
-                             target_version_prefix,
-                             rollback_allowed,
-                             rollback_data_save_requested,
-                             rollback_allowed_milestones,
-                             rollback_on_channel_downgrade,
-                             obey_proxies,
-                             interactive)) {
+  if (!CalculateUpdateParams(params)) {
     return;
   }
 
-  BuildUpdateActions(interactive);
+  BuildUpdateActions(params.interactive);
 
   SetStatusAndNotify(UpdateStatus::CHECKING_FOR_UPDATE);
 
@@ -360,17 +340,7 @@
   payload_state->SetUsingP2PForSharing(use_p2p_for_sharing);
 }
 
-bool UpdateAttempter::CalculateUpdateParams(const string& app_version,
-                                            const string& omaha_url,
-                                            const string& target_channel,
-                                            const string& lts_tag,
-                                            const string& target_version_prefix,
-                                            bool rollback_allowed,
-                                            bool rollback_data_save_requested,
-                                            int rollback_allowed_milestones,
-                                            bool rollback_on_channel_downgrade,
-                                            bool obey_proxies,
-                                            bool interactive) {
+bool UpdateAttempter::CalculateUpdateParams(const UpdateCheckParams& params) {
   http_response_code_ = 0;
   PayloadStateInterface* const payload_state = system_state_->payload_state();
 
@@ -381,30 +351,13 @@
   // policy is available again.
   UpdateRollbackHappened();
 
-  // Update the target version prefix.
-  omaha_request_params_->set_target_version_prefix(target_version_prefix);
-
-  // Update the LTS support.
-  omaha_request_params_->set_lts_tag(lts_tag);
-
-  // Set whether rollback is allowed.
-  omaha_request_params_->set_rollback_allowed(rollback_allowed);
-
-  // Set whether saving data over rollback is requested.
-  omaha_request_params_->set_rollback_data_save_requested(
-      rollback_data_save_requested);
-
-  CalculateStagingParams(interactive);
+  CalculateStagingParams(params.interactive);
   // If staging_wait_time_ wasn't set, staging is off, use scattering instead.
   if (staging_wait_time_.InSeconds() == 0) {
-    CalculateScatteringParams(interactive);
+    CalculateScatteringParams(params.interactive);
   }
 
-  // Set how many milestones of rollback are allowed.
-  omaha_request_params_->set_rollback_allowed_milestones(
-      rollback_allowed_milestones);
-
-  CalculateP2PParams(interactive);
+  CalculateP2PParams(params.interactive);
   if (payload_state->GetUsingP2PForDownloading() ||
       payload_state->GetUsingP2PForSharing()) {
     // OK, p2p is to be used - start it and perform housekeeping.
@@ -417,30 +370,12 @@
     }
   }
 
-  if (!omaha_request_params_->Init(app_version, omaha_url, interactive)) {
+  if (!omaha_request_params_->Init(
+          forced_app_version_, forced_omaha_url_, params)) {
     LOG(ERROR) << "Unable to initialize Omaha request params.";
     return false;
   }
 
-  // Set the target channel, if one was provided.
-  if (target_channel.empty()) {
-    LOG(INFO) << "No target channel mandated by policy.";
-  } else {
-    LOG(INFO) << "Setting target channel as mandated: " << target_channel;
-    string error_message;
-    if (!omaha_request_params_->SetTargetChannel(
-            target_channel, rollback_on_channel_downgrade, &error_message)) {
-      LOG(ERROR) << "Setting the channel failed: " << error_message;
-    }
-
-    // Since this is the beginning of a new attempt, update the download
-    // channel. The download channel won't be updated until the next attempt,
-    // even if target channel changes meanwhile, so that how we'll know if we
-    // should cancel the current download attempt if there's such a change in
-    // target channel.
-    omaha_request_params_->UpdateDownloadChannel();
-  }
-
   // The function |CalculateDlcParams| makes use of the function |GetAppId| from
   // |OmahaRequestParams|, so to ensure that the return from |GetAppId|
   // doesn't change, no changes to the values |download_channel_|,
@@ -448,8 +383,6 @@
   // |omaha_request_params_| shall be made below this line.
   CalculateDlcParams();
 
-  omaha_request_params_->set_is_install(is_install_);
-
   // Set Quick Fix Build token if policy is set and the device is enterprise
   // enrolled.
   string token;
@@ -480,7 +413,7 @@
             << payload_state->GetUsingP2PForSharing();
 
   obeying_proxies_ = true;
-  if (obey_proxies || proxy_manual_checks_ == 0) {
+  if (proxy_manual_checks_ == 0) {
     LOG(INFO) << "forced to obey proxies";
     // If forced to obey proxies, every 20th request will not use proxies
     proxy_manual_checks_++;
@@ -767,6 +700,7 @@
     dlc_apps_params[omaha_request_params_->GetDlcAppId(dlc_id)] = dlc_params;
   }
   omaha_request_params_->set_dlc_apps_params(dlc_apps_params);
+  omaha_request_params_->set_is_install(is_install_);
 }
 
 void UpdateAttempter::BuildUpdateActions(bool interactive) {
@@ -881,7 +815,7 @@
   processor_->set_delegate(this);
 
   // Initialize the default request params.
-  if (!omaha_request_params_->Init("", "", true)) {
+  if (!omaha_request_params_->Init("", "", {.interactive = true})) {
     LOG(ERROR) << "Unable to initialize Omaha request params.";
     return false;
   }
@@ -1107,17 +1041,7 @@
     LOG(INFO) << "Update attempt flags in use = 0x" << std::hex
               << current_update_attempt_flags_;
 
-    Update(forced_app_version_,
-           forced_omaha_url_,
-           params.target_channel,
-           params.lts_tag,
-           params.target_version_prefix,
-           params.rollback_allowed,
-           params.rollback_data_save_requested,
-           params.rollback_allowed_milestones,
-           params.rollback_on_channel_downgrade,
-           /*obey_proxies=*/false,
-           params.interactive);
+    Update(params);
     // Always clear the forced app_version and omaha_url after an update attempt
     // so the next update uses the defaults.
     forced_app_version_.clear();
diff --git a/update_attempter.h b/update_attempter.h
index 6c93150..3a1bef4 100644
--- a/update_attempter.h
+++ b/update_attempter.h
@@ -76,23 +76,8 @@
   virtual bool ScheduleUpdates();
 
   // Checks for update and, if a newer version is available, attempts to update
-  // the system. Non-empty |in_app_version| or |in_update_url| prevents
-  // automatic detection of the parameter.  |target_channel| denotes a
-  // policy-mandated channel we are updating to, if not empty. If |obey_proxies|
-  // is true, the update will likely respect Chrome's proxy setting. For
-  // security reasons, we may still not honor them. |interactive| should be true
-  // if this was called from the user (ie dbus).
-  virtual void Update(const std::string& app_version,
-                      const std::string& omaha_url,
-                      const std::string& target_channel,
-                      const std::string& lts_tag,
-                      const std::string& target_version_prefix,
-                      bool rollback_allowed,
-                      bool rollback_data_save_requested,
-                      int rollback_allowed_milestones,
-                      bool rollback_on_channel_downgrade,
-                      bool obey_proxies,
-                      bool interactive);
+  // the system.
+  virtual void Update(const chromeos_update_manager::UpdateCheckParams& params);
 
   // ActionProcessorDelegate methods:
   void ProcessingDone(const ActionProcessor* processor,
@@ -371,17 +356,8 @@
   // Helper method of Update() to calculate the update-related parameters
   // from various sources and set the appropriate state. Please refer to
   // Update() method for the meaning of the parameters.
-  bool CalculateUpdateParams(const std::string& app_version,
-                             const std::string& omaha_url,
-                             const std::string& target_channel,
-                             const std::string& lts_tag,
-                             const std::string& target_version_prefix,
-                             bool rollback_allowed,
-                             bool rollback_data_save_requested,
-                             int rollback_allowed_milestones,
-                             bool rollback_on_channel_downgrade,
-                             bool obey_proxies,
-                             bool interactive);
+  bool CalculateUpdateParams(
+      const chromeos_update_manager::UpdateCheckParams& params);
 
   // Calculates all the scattering related parameters (such as waiting period,
   // which type of scattering is enabled, etc.) and also updates/deletes
diff --git a/update_attempter_unittest.cc b/update_attempter_unittest.cc
index 60267f0..767bb82 100644
--- a/update_attempter_unittest.cc
+++ b/update_attempter_unittest.cc
@@ -172,30 +172,10 @@
   explicit UpdateAttempterUnderTest(SystemState* system_state)
       : UpdateAttempter(system_state, nullptr) {}
 
-  void Update(const std::string& app_version,
-              const std::string& omaha_url,
-              const std::string& target_channel,
-              const std::string& lts_tag,
-              const std::string& target_version_prefix,
-              bool rollback_allowed,
-              bool rollback_data_save_requested,
-              int rollback_allowed_milestones,
-              bool rollback_on_channel_downgrade,
-              bool obey_proxies,
-              bool interactive) override {
+  void Update(const UpdateCheckParams& params) override {
     update_called_ = true;
     if (do_update_) {
-      UpdateAttempter::Update(app_version,
-                              omaha_url,
-                              target_channel,
-                              lts_tag,
-                              target_version_prefix,
-                              rollback_allowed,
-                              rollback_data_save_requested,
-                              rollback_allowed_milestones,
-                              rollback_on_channel_downgrade,
-                              obey_proxies,
-                              interactive);
+      UpdateAttempter::Update(params);
       return;
     }
     LOG(INFO) << "[TEST] Update() disabled.";
@@ -430,7 +410,7 @@
 void UpdateAttempterTest::SessionIdTestChange() {
   EXPECT_NE(UpdateStatus::UPDATED_NEED_REBOOT, attempter_.status());
   const auto old_session_id = attempter_.session_id_;
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   EXPECT_NE(old_session_id, attempter_.session_id_);
   ScheduleQuitMainLoop();
 }
@@ -801,7 +781,7 @@
     EXPECT_CALL(*processor_, StartProcessing());
   }
 
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   loop_.PostTask(FROM_HERE,
                  base::Bind(&UpdateAttempterTest::UpdateTestVerify,
                             base::Unretained(this)));
@@ -1001,7 +981,7 @@
   fake_system_state_.set_p2p_manager(&mock_p2p_manager);
   mock_p2p_manager.fake().SetP2PEnabled(false);
   EXPECT_CALL(mock_p2p_manager, PerformHousekeeping()).Times(0);
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   EXPECT_FALSE(actual_using_p2p_for_downloading_);
   EXPECT_FALSE(actual_using_p2p_for_sharing());
   ScheduleQuitMainLoop();
@@ -1023,7 +1003,7 @@
   mock_p2p_manager.fake().SetEnsureP2PRunningResult(false);
   mock_p2p_manager.fake().SetPerformHousekeepingResult(false);
   EXPECT_CALL(mock_p2p_manager, PerformHousekeeping()).Times(0);
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   EXPECT_FALSE(actual_using_p2p_for_downloading());
   EXPECT_FALSE(actual_using_p2p_for_sharing());
   ScheduleQuitMainLoop();
@@ -1046,7 +1026,7 @@
   mock_p2p_manager.fake().SetEnsureP2PRunningResult(true);
   mock_p2p_manager.fake().SetPerformHousekeepingResult(false);
   EXPECT_CALL(mock_p2p_manager, PerformHousekeeping());
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   EXPECT_FALSE(actual_using_p2p_for_downloading());
   EXPECT_FALSE(actual_using_p2p_for_sharing());
   ScheduleQuitMainLoop();
@@ -1068,7 +1048,7 @@
   mock_p2p_manager.fake().SetEnsureP2PRunningResult(true);
   mock_p2p_manager.fake().SetPerformHousekeepingResult(true);
   EXPECT_CALL(mock_p2p_manager, PerformHousekeeping());
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   EXPECT_TRUE(actual_using_p2p_for_downloading());
   EXPECT_TRUE(actual_using_p2p_for_sharing());
   ScheduleQuitMainLoop();
@@ -1091,17 +1071,7 @@
   mock_p2p_manager.fake().SetEnsureP2PRunningResult(true);
   mock_p2p_manager.fake().SetPerformHousekeepingResult(true);
   EXPECT_CALL(mock_p2p_manager, PerformHousekeeping());
-  attempter_.Update("",
-                    "",
-                    "",
-                    "",
-                    "",
-                    false,
-                    false,
-                    /*rollback_allowed_milestones=*/0,
-                    false,
-                    false,
-                    /*interactive=*/true);
+  attempter_.Update({.interactive = true});
   EXPECT_FALSE(actual_using_p2p_for_downloading());
   EXPECT_TRUE(actual_using_p2p_for_sharing());
   ScheduleQuitMainLoop();
@@ -1131,7 +1101,7 @@
   attempter_.policy_provider_.reset(
       new policy::PolicyProvider(std::move(device_policy)));
 
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   EXPECT_EQ(scatter_factor_in_seconds, attempter_.scatter_factor_.InSeconds());
 
   ScheduleQuitMainLoop();
@@ -1169,7 +1139,7 @@
   attempter_.policy_provider_.reset(
       new policy::PolicyProvider(std::move(device_policy)));
 
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   EXPECT_EQ(scatter_factor_in_seconds, attempter_.scatter_factor_.InSeconds());
 
   // Make sure the file still exists.
@@ -1185,7 +1155,7 @@
   // However, if the count is already 0, it's not decremented. Test that.
   initial_value = 0;
   EXPECT_TRUE(fake_prefs.SetInt64(kPrefsUpdateCheckCount, initial_value));
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   EXPECT_TRUE(fake_prefs.Exists(kPrefsUpdateCheckCount));
   EXPECT_TRUE(fake_prefs.GetInt64(kPrefsUpdateCheckCount, &new_value));
   EXPECT_EQ(initial_value, new_value);
@@ -1232,17 +1202,7 @@
       new policy::PolicyProvider(std::move(device_policy)));
 
   // Trigger an interactive check so we can test that scattering is disabled.
-  attempter_.Update("",
-                    "",
-                    "",
-                    "",
-                    "",
-                    false,
-                    false,
-                    /*rollback_allowed_milestones=*/0,
-                    false,
-                    false,
-                    /*interactive=*/true);
+  attempter_.Update({.interactive = true});
   EXPECT_EQ(scatter_factor_in_seconds, attempter_.scatter_factor_.InSeconds());
 
   // Make sure scattering is disabled for manual (i.e. user initiated) update
@@ -1294,7 +1254,7 @@
   FakePrefs fake_prefs;
   SetUpStagingTest(kValidStagingSchedule, &fake_prefs);
 
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   // Check that prefs have the correct values.
   int64_t update_count;
   EXPECT_TRUE(fake_prefs.GetInt64(kPrefsUpdateCheckCount, &update_count));
@@ -1351,17 +1311,7 @@
   FakePrefs fake_prefs;
   SetUpStagingTest(kValidStagingSchedule, &fake_prefs);
 
-  attempter_.Update("",
-                    "",
-                    "",
-                    "",
-                    "",
-                    false,
-                    false,
-                    0,
-                    false,
-                    false,
-                    /* interactive = */ true);
+  attempter_.Update({.interactive = true});
   CheckStagingOff();
 
   ScheduleQuitMainLoop();
@@ -1381,17 +1331,7 @@
   FakePrefs fake_prefs;
   SetUpStagingTest(kValidStagingSchedule, &fake_prefs);
 
-  attempter_.Update("",
-                    "",
-                    "",
-                    "",
-                    "",
-                    false,
-                    false,
-                    0,
-                    false,
-                    false,
-                    /* interactive = */ true);
+  attempter_.Update({.interactive = true});
   CheckStagingOff();
 
   ScheduleQuitMainLoop();
@@ -1719,64 +1659,38 @@
 }
 
 TEST_F(UpdateAttempterTest, TargetVersionPrefixSetAndReset) {
-  attempter_.CalculateUpdateParams(
-      /*app_version=*/"",
-      /*omaha_url=*/"",
-      /*target_channel=*/"",
-      /*lts_tag=*/"",
-      /*target_version_prefix=*/"1234",
-      /*rollback_allowed=*/false,
-      /*rollback_data_save_requested=*/false,
-      /*rollback_allowed_milestones=*/4,
-      /*rollback_on_channel_downgrade=*/false,
-      /*obey_proxies=*/false,
-      /*interactive=*/false);
+  UpdateCheckParams params;
+  attempter_.CalculateUpdateParams({.target_version_prefix = "1234"});
   EXPECT_EQ("1234",
             fake_system_state_.request_params()->target_version_prefix());
 
-  attempter_.CalculateUpdateParams(
-      "", "", "", "", "", false, false, 4, false, false, false);
+  attempter_.CalculateUpdateParams({});
   EXPECT_TRUE(
       fake_system_state_.request_params()->target_version_prefix().empty());
 }
 
 TEST_F(UpdateAttempterTest, TargetChannelHintSetAndReset) {
-  attempter_.CalculateUpdateParams(
-      "", "", "", "hint", "", false, false, 4, false, false, false);
+  attempter_.CalculateUpdateParams({.lts_tag = "hint"});
   EXPECT_EQ("hint", fake_system_state_.request_params()->lts_tag());
 
-  attempter_.CalculateUpdateParams(
-      "", "", "", "", "", false, false, 4, false, false, false);
+  attempter_.CalculateUpdateParams({});
   EXPECT_TRUE(fake_system_state_.request_params()->lts_tag().empty());
 }
 
 TEST_F(UpdateAttempterTest, RollbackAllowedSetAndReset) {
-  attempter_.CalculateUpdateParams("",
-                                   "",
-                                   "",
-                                   "",
-                                   "1234",
-                                   /*rollback_allowed=*/true,
-                                   /*rollback_data_save_requested=*/false,
-                                   /*rollback_allowed_milestones=*/4,
-                                   /*rollback_on_channel_downgrade=*/false,
-                                   false,
-                                   false);
+  attempter_.CalculateUpdateParams({
+      .target_version_prefix = "1234",
+      .rollback_allowed = true,
+      .rollback_allowed_milestones = 4,
+  });
   EXPECT_TRUE(fake_system_state_.request_params()->rollback_allowed());
   EXPECT_EQ(4,
             fake_system_state_.request_params()->rollback_allowed_milestones());
 
-  attempter_.CalculateUpdateParams("",
-                                   "",
-                                   "",
-                                   "",
-                                   "1234",
-                                   /*rollback_allowed=*/false,
-                                   /*rollback_data_save_requested=*/false,
-                                   /*rollback_allowed_milestones=*/4,
-                                   /*rollback_on_channel_downgrade=*/false,
-                                   false,
-                                   false);
+  attempter_.CalculateUpdateParams({
+      .target_version_prefix = "1234",
+      .rollback_allowed_milestones = 4,
+  });
   EXPECT_FALSE(fake_system_state_.request_params()->rollback_allowed());
   EXPECT_EQ(4,
             fake_system_state_.request_params()->rollback_allowed_milestones());
@@ -1786,17 +1700,9 @@
   base::ScopedTempDir tempdir;
   ASSERT_TRUE(tempdir.CreateUniqueTempDir());
   fake_system_state_.request_params()->set_root(tempdir.GetPath().value());
-  attempter_.CalculateUpdateParams(/*app_version=*/"",
-                                   /*omaha_url=*/"",
-                                   /*target_channel=*/"stable-channel",
-                                   /*lts_tag=*/"",
-                                   /*target_version_prefix=*/"",
-                                   /*rollback_allowed=*/false,
-                                   /*rollback_data_save_requested=*/false,
-                                   /*rollback_allowed_milestones=*/4,
-                                   /*rollback_on_channel_downgrade=*/false,
-                                   /*obey_proxies=*/false,
-                                   /*interactive=*/false);
+  attempter_.CalculateUpdateParams({
+      .target_channel = "stable-channel",
+  });
   EXPECT_FALSE(fake_system_state_.request_params()->is_powerwash_allowed());
 }
 
@@ -1804,17 +1710,10 @@
   base::ScopedTempDir tempdir;
   ASSERT_TRUE(tempdir.CreateUniqueTempDir());
   fake_system_state_.request_params()->set_root(tempdir.GetPath().value());
-  attempter_.CalculateUpdateParams(/*app_version=*/"",
-                                   /*omaha_url=*/"",
-                                   /*target_channel=*/"stable-channel",
-                                   /*lts_tag=*/"",
-                                   /*target_version_prefix=*/"",
-                                   /*rollback_allowed=*/false,
-                                   /*rollback_data_save_requested=*/false,
-                                   /*rollback_allowed_milestones=*/4,
-                                   /*rollback_on_channel_downgrade=*/true,
-                                   /*obey_proxies=*/false,
-                                   /*interactive=*/false);
+  attempter_.CalculateUpdateParams({
+      .rollback_on_channel_downgrade = true,
+      .target_channel = "stable-channel",
+  });
   EXPECT_TRUE(fake_system_state_.request_params()->is_powerwash_allowed());
 }
 
@@ -1932,7 +1831,7 @@
               SetRollbackHappened(false))
       .Times(expected_reset ? 1 : 0);
   attempter_.policy_provider_ = std::move(mock_policy_provider);
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
   ScheduleQuitMainLoop();
 }
 
@@ -2273,7 +2172,7 @@
         .WillOnce(Return(false));
   attempter_.policy_provider_.reset(
       new policy::PolicyProvider(std::move(device_policy)));
-  attempter_.Update("", "", "", "", "", false, false, 0, false, false, false);
+  attempter_.Update({});
 
   EXPECT_EQ(token, attempter_.omaha_request_params_->autoupdate_token());
   ScheduleQuitMainLoop();
diff --git a/update_manager/policy.h b/update_manager/policy.h
index 4b3bfc7..ad6994c 100644
--- a/update_manager/policy.h
+++ b/update_manager/policy.h
@@ -43,21 +43,22 @@
 // Parameters of an update check. These parameters are determined by the
 // UpdateCheckAllowed policy.
 struct UpdateCheckParams {
-  bool updates_enabled;  // Whether the auto-updates are enabled on this build.
+  // Whether the auto-updates are enabled on this build.
+  bool updates_enabled{true};
 
   // Attributes pertaining to the case where update checks are allowed.
   //
   // A target version prefix, if imposed by policy; otherwise, an empty string.
   std::string target_version_prefix;
   // Specifies whether rollback images are allowed by device policy.
-  bool rollback_allowed;
+  bool rollback_allowed{false};
   // Specifies if rollbacks should attempt to preserve some system state.
-  bool rollback_data_save_requested;
+  bool rollback_data_save_requested{false};
   // Specifies the number of Chrome milestones rollback should be allowed,
   // starting from the stable version at any time. Value is -1 if unspecified
   // (e.g. no device policy is available yet), in this case no version
   // roll-forward should happen.
-  int rollback_allowed_milestones;
+  int rollback_allowed_milestones{0};
   // Whether a rollback with data save should be initiated on channel
   // downgrade (e.g. beta to stable).
   bool rollback_on_channel_downgrade{false};
@@ -67,7 +68,7 @@
   std::string lts_tag;
 
   // Whether the allowed update is interactive (user-initiated) or periodic.
-  bool interactive;
+  bool interactive{false};
 };
 
 // Input arguments to UpdateCanStart.
diff --git a/update_manager/real_updater_provider_unittest.cc b/update_manager/real_updater_provider_unittest.cc
index f0804c4..06808b8 100644
--- a/update_manager/real_updater_provider_unittest.cc
+++ b/update_manager/real_updater_provider_unittest.cc
@@ -327,7 +327,7 @@
 TEST_F(UmRealUpdaterProviderTest, GetCurrChannelOkay) {
   const string kChannelName("foo-channel");
   OmahaRequestParams request_params(&fake_sys_state_);
-  request_params.Init("", "", false);
+  request_params.Init("", "", {});
   request_params.set_current_channel(kChannelName);
   fake_sys_state_.set_request_params(&request_params);
   UmTestUtils::ExpectVariableHasValue(kChannelName,
@@ -336,7 +336,7 @@
 
 TEST_F(UmRealUpdaterProviderTest, GetCurrChannelFailEmpty) {
   OmahaRequestParams request_params(&fake_sys_state_);
-  request_params.Init("", "", false);
+  request_params.Init("", "", {});
   request_params.set_current_channel("");
   fake_sys_state_.set_request_params(&request_params);
   UmTestUtils::ExpectVariableNotSet(provider_->var_curr_channel());
@@ -345,7 +345,7 @@
 TEST_F(UmRealUpdaterProviderTest, GetNewChannelOkay) {
   const string kChannelName("foo-channel");
   OmahaRequestParams request_params(&fake_sys_state_);
-  request_params.Init("", "", false);
+  request_params.Init("", "", {});
   request_params.set_target_channel(kChannelName);
   fake_sys_state_.set_request_params(&request_params);
   UmTestUtils::ExpectVariableHasValue(kChannelName,
@@ -354,7 +354,7 @@
 
 TEST_F(UmRealUpdaterProviderTest, GetNewChannelFailEmpty) {
   OmahaRequestParams request_params(&fake_sys_state_);
-  request_params.Init("", "", false);
+  request_params.Init("", "", {});
   request_params.set_target_channel("");
   fake_sys_state_.set_request_params(&request_params);
   UmTestUtils::ExpectVariableNotSet(provider_->var_new_channel());