diff --git a/common/dynamic_partition_control_interface.h b/common/dynamic_partition_control_interface.h
index 7c2d0b0..f47958d 100644
--- a/common/dynamic_partition_control_interface.h
+++ b/common/dynamic_partition_control_interface.h
@@ -26,6 +26,7 @@
 #include "update_engine/common/action.h"
 #include "update_engine/common/cleanup_previous_update_action_delegate.h"
 #include "update_engine/common/error_code.h"
+#include "update_engine/common/prefs_interface.h"
 #include "update_engine/update_metadata.pb.h"
 
 namespace chromeos_update_engine {
@@ -42,7 +43,6 @@
 };
 
 class BootControlInterface;
-class PrefsInterface;
 
 class DynamicPartitionControlInterface {
  public:
diff --git a/cros/omaha_request_action.cc b/cros/omaha_request_action.cc
index 6f270c0..f847194 100644
--- a/cros/omaha_request_action.cc
+++ b/cros/omaha_request_action.cc
@@ -456,19 +456,17 @@
     return;
   }
 
-  auto* params = SystemState::Get()->request_params();
   OmahaRequestBuilderXml omaha_request(event_.get(),
-                                       params,
                                        ping_only_,
                                        ShouldPing(),  // include_ping
                                        ping_active_days_,
                                        ping_roll_call_days_,
                                        GetInstallDate(),
-                                       SystemState::Get()->prefs(),
                                        session_id_);
   string request_post = omaha_request.GetRequest();
 
   // Set X-Goog-Update headers.
+  const auto* params = SystemState::Get()->request_params();
   http_fetcher_->SetHeader(kXGoogleUpdateInteractivity,
                            params->interactive() ? "fg" : "bg");
   http_fetcher_->SetHeader(kXGoogleUpdateAppId, params->GetAppId());
diff --git a/cros/omaha_request_builder_xml.cc b/cros/omaha_request_builder_xml.cc
index 739abbf..6cd9ab8 100644
--- a/cros/omaha_request_builder_xml.cc
+++ b/cros/omaha_request_builder_xml.cc
@@ -28,7 +28,7 @@
 #include <base/time/time.h>
 
 #include "update_engine/common/constants.h"
-#include "update_engine/common/prefs_interface.h"
+#include "update_engine/common/system_state.h"
 #include "update_engine/common/utils.h"
 #include "update_engine/cros/omaha_request_params.h"
 
@@ -144,20 +144,21 @@
     }
     if (!ping_only_) {
       if (!app_data.skip_update) {
+        const auto* params = SystemState::Get()->request_params();
         app_body += "        <updatecheck";
-        if (!params_->target_version_prefix().empty()) {
+        if (!params->target_version_prefix().empty()) {
           app_body += base::StringPrintf(
               " targetversionprefix=\"%s\"",
-              XmlEncodeWithDefault(params_->target_version_prefix()).c_str());
+              XmlEncodeWithDefault(params->target_version_prefix()).c_str());
           // Rollback requires target_version_prefix set.
-          if (params_->rollback_allowed()) {
+          if (params->rollback_allowed()) {
             app_body += " rollback_allowed=\"true\"";
           }
         }
-        if (!params_->lts_tag().empty()) {
+        if (!params->lts_tag().empty()) {
           app_body += base::StringPrintf(
               " ltstag=\"%s\"",
-              XmlEncodeWithDefault(params_->lts_tag()).c_str());
+              XmlEncodeWithDefault(params->lts_tag()).c_str());
         }
         app_body += "></updatecheck>\n";
       }
@@ -170,8 +171,9 @@
       // for ping-only requests because they come before the client has
       // rebooted. The previous version event is also not sent if it was already
       // sent for this new version with a previous updatecheck.
+      auto* prefs = SystemState::Get()->prefs();
       string prev_version;
-      if (!prefs_->GetString(kPrefsPreviousVersion, &prev_version)) {
+      if (!prefs->GetString(kPrefsPreviousVersion, &prev_version)) {
         prev_version = kNoVersion;
       }
       // We only store a non-empty previous version value after a successful
@@ -184,7 +186,7 @@
             OmahaEvent::kTypeRebootedAfterUpdate,
             OmahaEvent::kResultSuccess,
             XmlEncodeWithDefault(prev_version, kNoVersion).c_str());
-        LOG_IF(WARNING, !prefs_->SetString(kPrefsPreviousVersion, ""))
+        LOG_IF(WARNING, !prefs->SetString(kPrefsPreviousVersion, ""))
             << "Unable to reset the previous version.";
       }
     }
@@ -226,9 +228,10 @@
   } else {
     // There's nothing wrong with not having a given cohort setting, so we check
     // existence first to avoid the warning log message.
-    if (!prefs_->Exists(prefs_key))
+    const auto* prefs = SystemState::Get()->prefs();
+    if (!prefs->Exists(prefs_key))
       return "";
-    if (!prefs_->GetString(prefs_key, &cohort_value) || cohort_value.empty())
+    if (!prefs->GetString(prefs_key, &cohort_value) || cohort_value.empty())
       return "";
   }
   // This is a validity check to avoid sending a huge XML file back to Ohama due
@@ -263,11 +266,12 @@
 string OmahaRequestBuilderXml::GetApp(const OmahaAppData& app_data) const {
   string app_body = GetAppBody(app_data);
   string app_versions;
+  const auto* params = SystemState::Get()->request_params();
 
   // If we are downgrading to a more stable channel and we are allowed to do
   // powerwash, then pass 0.0.0.0 as the version. This is needed to get the
   // highest-versioned payload on the destination channel.
-  if (params_->ShouldPowerwash()) {
+  if (params->ShouldPowerwash()) {
     LOG(INFO) << "Passing OS version as 0.0.0.0 as we are set to powerwash "
               << "on downgrading to the version in the more stable channel";
     app_versions = "version=\"" + string(kNoVersion) + "\" from_version=\"" +
@@ -277,16 +281,16 @@
                    XmlEncodeWithDefault(app_data.version, kNoVersion) + "\" ";
   }
 
-  string download_channel = params_->download_channel();
+  string download_channel = params->download_channel();
   string app_channels =
       "track=\"" + XmlEncodeWithDefault(download_channel) + "\" ";
-  if (params_->current_channel() != download_channel) {
+  if (params->current_channel() != download_channel) {
     app_channels += "from_track=\"" +
-                    XmlEncodeWithDefault(params_->current_channel()) + "\" ";
+                    XmlEncodeWithDefault(params->current_channel()) + "\" ";
   }
 
   string delta_okay_str =
-      params_->delta_okay() && !params_->is_install() ? "true" : "false";
+      params->delta_okay() && !params->is_install() ? "true" : "false";
 
   // If install_date_days is not set (e.g. its value is -1 ), don't
   // include the attribute.
@@ -302,16 +306,17 @@
   string cohorthint_key = kPrefsOmahaCohortHint;
 
   // Override the cohort keys for DLC App IDs.
-  const auto& dlc_apps_params = params_->dlc_apps_params();
+  const auto& dlc_apps_params = params->dlc_apps_params();
   auto itr = dlc_apps_params.find(app_data.id);
   if (itr != dlc_apps_params.end()) {
     auto dlc_id = itr->second.name;
+    const auto* prefs = SystemState::Get()->prefs();
     cohort_key =
-        prefs_->CreateSubKey({kDlcPrefsSubDir, dlc_id, kPrefsOmahaCohort});
+        prefs->CreateSubKey({kDlcPrefsSubDir, dlc_id, kPrefsOmahaCohort});
     cohortname_key =
-        prefs_->CreateSubKey({kDlcPrefsSubDir, dlc_id, kPrefsOmahaCohortName});
+        prefs->CreateSubKey({kDlcPrefsSubDir, dlc_id, kPrefsOmahaCohortName});
     cohorthint_key =
-        prefs_->CreateSubKey({kDlcPrefsSubDir, dlc_id, kPrefsOmahaCohortHint});
+        prefs->CreateSubKey({kDlcPrefsSubDir, dlc_id, kPrefsOmahaCohortHint});
   }
 
   app_cohort_args += GetCohortArg("cohort", cohort_key);
@@ -320,23 +325,23 @@
   app_cohort_args +=
       GetCohortArg("cohorthint",
                    cohorthint_key,
-                   params_->autoupdate_token() /* override_value */);
+                   params->autoupdate_token() /* override_value */);
 
   string fingerprint_arg;
-  if (!params_->os_build_fingerprint().empty()) {
+  if (!params->os_build_fingerprint().empty()) {
     fingerprint_arg = "fingerprint=\"" +
-                      XmlEncodeWithDefault(params_->os_build_fingerprint()) +
+                      XmlEncodeWithDefault(params->os_build_fingerprint()) +
                       "\" ";
   }
 
   string buildtype_arg;
-  if (!params_->os_build_type().empty()) {
+  if (!params->os_build_type().empty()) {
     buildtype_arg = "os_build_type=\"" +
-                    XmlEncodeWithDefault(params_->os_build_type()) + "\" ";
+                    XmlEncodeWithDefault(params->os_build_type()) + "\" ";
   }
 
   string product_components_args;
-  if (!params_->ShouldPowerwash() && !app_data.product_components.empty()) {
+  if (!params->ShouldPowerwash() && !app_data.product_components.empty()) {
     brillo::KeyValueStore store;
     if (store.LoadFromString(app_data.product_components)) {
       for (const string& key : store.GetKeys()) {
@@ -362,9 +367,9 @@
   }
 
   string requisition_arg;
-  if (!params_->device_requisition().empty()) {
+  if (!params->device_requisition().empty()) {
     requisition_arg = "requisition=\"" +
-                      XmlEncodeWithDefault(params_->device_requisition()) +
+                      XmlEncodeWithDefault(params->device_requisition()) +
                       "\" ";
   }
 
@@ -377,14 +382,14 @@
       product_components_args +
       fingerprint_arg +
       buildtype_arg +
-      "board=\"" + XmlEncodeWithDefault(params_->os_board()) + "\" " +
-      "hardware_class=\"" + XmlEncodeWithDefault(params_->hwid()) + "\" " +
+      "board=\"" + XmlEncodeWithDefault(params->os_board()) + "\" " +
+      "hardware_class=\"" + XmlEncodeWithDefault(params->hwid()) + "\" " +
       "delta_okay=\"" + delta_okay_str + "\" " +
       install_date_in_days_str +
 
       // DLC excluded for installs and updates.
       (app_data.is_dlc ? "" :
-      "lang=\"" + XmlEncodeWithDefault(params_->app_lang(), "en-US") + "\" " +
+      "lang=\"" + XmlEncodeWithDefault(params->app_lang(), "en-US") + "\" " +
       requisition_arg) +
 
       ">\n" +
@@ -395,18 +400,20 @@
 }
 
 string OmahaRequestBuilderXml::GetOs() const {
+  const auto* params = SystemState::Get()->request_params();
   string os_xml =
       "    <os "
       "version=\"" +
-      XmlEncodeWithDefault(params_->os_version()) + "\" " + "platform=\"" +
-      XmlEncodeWithDefault(params_->os_platform()) + "\" " + "sp=\"" +
-      XmlEncodeWithDefault(params_->os_sp()) +
+      XmlEncodeWithDefault(params->os_version()) + "\" " + "platform=\"" +
+      XmlEncodeWithDefault(params->os_platform()) + "\" " + "sp=\"" +
+      XmlEncodeWithDefault(params->os_sp()) +
       "\">"
       "</os>\n";
   return os_xml;
 }
 
 string OmahaRequestBuilderXml::GetRequest() const {
+  const auto* params = SystemState::Get()->request_params();
   string os_xml = GetOs();
   string app_xml = GetApps();
 
@@ -419,7 +426,7 @@
       session_id_.c_str(),
       constants::kOmahaUpdaterID,
       kOmahaUpdaterVersion,
-      params_->interactive() ? "ondemandupdate" : "scheduler",
+      params->interactive() ? "ondemandupdate" : "scheduler",
       os_xml.c_str(),
       app_xml.c_str());
 
@@ -427,22 +434,23 @@
 }
 
 string OmahaRequestBuilderXml::GetApps() const {
+  const auto* params = SystemState::Get()->request_params();
   string app_xml = "";
   OmahaAppData product_app = {
-      .id = params_->GetAppId(),
-      .version = params_->app_version(),
-      .product_components = params_->product_components(),
+      .id = params->GetAppId(),
+      .version = params->app_version(),
+      .product_components = params->product_components(),
       // Skips updatecheck for platform app in case of an install operation.
-      .skip_update = params_->is_install(),
+      .skip_update = params->is_install(),
       .is_dlc = false,
 
       .app_params = {.active_counting_type = OmahaRequestParams::kDayBased,
                      .send_ping = include_ping_}};
   app_xml += GetApp(product_app);
-  for (const auto& it : params_->dlc_apps_params()) {
+  for (const auto& it : params->dlc_apps_params()) {
     OmahaAppData dlc_app_data = {
         .id = it.first,
-        .version = params_->is_install() ? kNoVersion : params_->app_version(),
+        .version = params->is_install() ? kNoVersion : params->app_version(),
         .skip_update = false,
         .is_dlc = true,
         .app_params = it.second};
diff --git a/cros/omaha_request_builder_xml.h b/cros/omaha_request_builder_xml.h
index 6bbc84e..7c246f7 100644
--- a/cros/omaha_request_builder_xml.h
+++ b/cros/omaha_request_builder_xml.h
@@ -121,22 +121,18 @@
 class OmahaRequestBuilderXml : OmahaRequestBuilder {
  public:
   OmahaRequestBuilderXml(const OmahaEvent* event,
-                         OmahaRequestParams* params,
                          bool ping_only,
                          bool include_ping,
                          int ping_active_days,
                          int ping_roll_call_days,
                          int install_date_in_days,
-                         PrefsInterface* prefs,
                          const std::string& session_id)
       : event_(event),
-        params_(params),
         ping_only_(ping_only),
         include_ping_(include_ping),
         ping_active_days_(ping_active_days),
         ping_roll_call_days_(ping_roll_call_days),
         install_date_in_days_(install_date_in_days),
-        prefs_(prefs),
         session_id_(session_id) {}
 
   ~OmahaRequestBuilderXml() override = default;
@@ -181,13 +177,11 @@
       const OmahaRequestParams::AppParams& app_params) const;
 
   const OmahaEvent* event_;
-  OmahaRequestParams* params_;
   bool ping_only_;
   bool include_ping_;
   int ping_active_days_;
   int ping_roll_call_days_;
   int install_date_in_days_;
-  PrefsInterface* prefs_;
   std::string session_id_;
 
   DISALLOW_COPY_AND_ASSIGN(OmahaRequestBuilderXml);
diff --git a/cros/omaha_request_builder_xml_unittest.cc b/cros/omaha_request_builder_xml_unittest.cc
index 74d616d..1ef0278 100644
--- a/cros/omaha_request_builder_xml_unittest.cc
+++ b/cros/omaha_request_builder_xml_unittest.cc
@@ -61,10 +61,15 @@
 
 class OmahaRequestBuilderXmlTest : public ::testing::Test {
  protected:
-  void SetUp() override { FakeSystemState::CreateInstance(); }
+  void SetUp() override {
+    FakeSystemState::CreateInstance();
+    FakeSystemState::Get()->set_request_params(&params_);
+  }
   void TearDown() override {}
 
   static constexpr size_t kGuidSize = 36;
+
+  OmahaRequestParams params_;
 };
 
 TEST_F(OmahaRequestBuilderXmlTest, XmlEncodeTest) {
@@ -93,16 +98,13 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, PlatformGetAppTest) {
-  OmahaRequestParams omaha_request_params;
-  omaha_request_params.set_device_requisition("device requisition");
+  params_.set_device_requisition("device requisition");
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   OmahaAppData dlc_app_data = {.id = "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX",
                                .version = "",
@@ -117,16 +119,13 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, DlcGetAppTest) {
-  OmahaRequestParams omaha_request_params;
-  omaha_request_params.set_device_requisition("device requisition");
+  params_.set_device_requisition("device requisition");
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   OmahaAppData dlc_app_data = {
       .id = "_dlc_id", .version = "", .skip_update = false, .is_dlc = true};
@@ -139,15 +138,12 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlRequestIdTest) {
-  OmahaRequestParams omaha_request_params;
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   const string key = "requestid";
@@ -160,15 +156,12 @@
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlSessionIdTest) {
   const string gen_session_id = base::GenerateGUID();
-  OmahaRequestParams omaha_request_params;
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        gen_session_id};
   const string request_xml = omaha_request.GetRequest();
   const string key = "sessionid";
@@ -182,15 +175,12 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlPlatformUpdateTest) {
-  OmahaRequestParams omaha_request_params;
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   EXPECT_EQ(1, CountSubstringInString(request_xml, "<updatecheck"))
@@ -198,18 +188,15 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlPlatformUpdateWithDlcsTest) {
-  OmahaRequestParams omaha_request_params;
-  omaha_request_params.set_dlc_apps_params(
-      {{omaha_request_params.GetDlcAppId("dlc_no_0"), {.name = "dlc_no_0"}},
-       {omaha_request_params.GetDlcAppId("dlc_no_1"), {.name = "dlc_no_1"}}});
+  params_.set_dlc_apps_params(
+      {{params_.GetDlcAppId("dlc_no_0"), {.name = "dlc_no_0"}},
+       {params_.GetDlcAppId("dlc_no_1"), {.name = "dlc_no_1"}}});
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   EXPECT_EQ(3, CountSubstringInString(request_xml, "<updatecheck"))
@@ -217,20 +204,17 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlDlcInstallationTest) {
-  OmahaRequestParams omaha_request_params;
   const std::map<std::string, OmahaRequestParams::AppParams> dlcs = {
-      {omaha_request_params.GetDlcAppId("dlc_no_0"), {.name = "dlc_no_0"}},
-      {omaha_request_params.GetDlcAppId("dlc_no_1"), {.name = "dlc_no_1"}}};
-  omaha_request_params.set_dlc_apps_params(dlcs);
-  omaha_request_params.set_is_install(true);
+      {params_.GetDlcAppId("dlc_no_0"), {.name = "dlc_no_0"}},
+      {params_.GetDlcAppId("dlc_no_1"), {.name = "dlc_no_1"}}};
+  params_.set_dlc_apps_params(dlcs);
+  params_.set_is_install(true);
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   EXPECT_EQ(2, CountSubstringInString(request_xml, "<updatecheck"))
@@ -256,39 +240,33 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlDlcNoPing) {
-  OmahaRequestParams omaha_request_params;
-  omaha_request_params.set_dlc_apps_params(
-      {{omaha_request_params.GetDlcAppId("dlc_no_0"), {.name = "dlc_no_0"}}});
+  params_.set_dlc_apps_params(
+      {{params_.GetDlcAppId("dlc_no_0"), {.name = "dlc_no_0"}}});
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   EXPECT_EQ(0, CountSubstringInString(request_xml, "<ping")) << request_xml;
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlDlcPingRollCallNoActive) {
-  OmahaRequestParams omaha_request_params;
-  omaha_request_params.set_dlc_apps_params(
-      {{omaha_request_params.GetDlcAppId("dlc_no_0"),
+  params_.set_dlc_apps_params(
+      {{params_.GetDlcAppId("dlc_no_0"),
         {.active_counting_type = OmahaRequestParams::kDateBased,
          .name = "dlc_no_0",
          .ping_date_last_active = 25,
          .ping_date_last_rollcall = 36,
          .send_ping = true}}});
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   EXPECT_EQ(1, CountSubstringInString(request_xml, "<ping rd=\"36\""))
@@ -296,9 +274,8 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlDlcPingRollCallAndActive) {
-  OmahaRequestParams omaha_request_params;
-  omaha_request_params.set_dlc_apps_params(
-      {{omaha_request_params.GetDlcAppId("dlc_no_0"),
+  params_.set_dlc_apps_params(
+      {{params_.GetDlcAppId("dlc_no_0"),
         {.active_counting_type = OmahaRequestParams::kDateBased,
          .name = "dlc_no_0",
          .ping_active = 1,
@@ -306,13 +283,11 @@
          .ping_date_last_rollcall = 36,
          .send_ping = true}}});
   OmahaRequestBuilderXml omaha_request{nullptr,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   EXPECT_EQ(1,
@@ -322,16 +297,13 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlUpdateCompleteEvent) {
-  OmahaRequestParams omaha_request_params;
   OmahaEvent event(OmahaEvent::kTypeUpdateComplete);
   OmahaRequestBuilderXml omaha_request{&event,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   LOG(INFO) << request_xml;
@@ -344,20 +316,17 @@
 
 TEST_F(OmahaRequestBuilderXmlTest,
        GetRequestXmlUpdateCompleteEventSomeDlcsExcluded) {
-  OmahaRequestParams omaha_request_params;
-  omaha_request_params.set_dlc_apps_params({
-      {omaha_request_params.GetDlcAppId("dlc_1"), {.updated = true}},
-      {omaha_request_params.GetDlcAppId("dlc_2"), {.updated = false}},
+  params_.set_dlc_apps_params({
+      {params_.GetDlcAppId("dlc_1"), {.updated = true}},
+      {params_.GetDlcAppId("dlc_2"), {.updated = false}},
   });
   OmahaEvent event(OmahaEvent::kTypeUpdateComplete);
   OmahaRequestBuilderXml omaha_request{&event,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   EXPECT_EQ(
@@ -375,20 +344,17 @@
 
 TEST_F(OmahaRequestBuilderXmlTest,
        GetRequestXmlUpdateCompleteEventAllDlcsExcluded) {
-  OmahaRequestParams omaha_request_params;
-  omaha_request_params.set_dlc_apps_params({
-      {omaha_request_params.GetDlcAppId("dlc_1"), {.updated = false}},
-      {omaha_request_params.GetDlcAppId("dlc_2"), {.updated = false}},
+  params_.set_dlc_apps_params({
+      {params_.GetDlcAppId("dlc_1"), {.updated = false}},
+      {params_.GetDlcAppId("dlc_2"), {.updated = false}},
   });
   OmahaEvent event(OmahaEvent::kTypeUpdateComplete);
   OmahaRequestBuilderXml omaha_request{&event,
-                                       &omaha_request_params,
                                        false,
                                        false,
                                        0,
                                        0,
                                        0,
-                                       FakeSystemState::Get()->prefs(),
                                        ""};
   const string request_xml = omaha_request.GetRequest();
   EXPECT_EQ(
@@ -405,14 +371,12 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlDlcCohortMissingCheck) {
-  OmahaRequestParams omaha_request_params;
   constexpr char kDlcId[] = "test-dlc-id";
-  omaha_request_params.set_dlc_apps_params(
-      {{omaha_request_params.GetDlcAppId(kDlcId), {.name = kDlcId}}});
+  params_.set_dlc_apps_params(
+      {{params_.GetDlcAppId(kDlcId), {.name = kDlcId}}});
   auto* mock_prefs = FakeSystemState::Get()->mock_prefs();
   OmahaEvent event(OmahaEvent::kTypeUpdateDownloadStarted);
-  OmahaRequestBuilderXml omaha_request{
-      &event, &omaha_request_params, false, false, 0, 0, 0, mock_prefs, ""};
+  OmahaRequestBuilderXml omaha_request{&event, false, false, 0, 0, 0, ""};
   // OS App ID Expectations.
   EXPECT_CALL(*mock_prefs, Exists(kPrefsOmahaCohort));
   EXPECT_CALL(*mock_prefs, Exists(kPrefsOmahaCohortName));
@@ -438,15 +402,13 @@
 }
 
 TEST_F(OmahaRequestBuilderXmlTest, GetRequestXmlDlcCohortCheck) {
-  OmahaRequestParams omaha_request_params;
   const string kDlcId = "test-dlc-id";
-  omaha_request_params.set_dlc_apps_params(
-      {{omaha_request_params.GetDlcAppId(kDlcId), {.name = kDlcId}}});
+  params_.set_dlc_apps_params(
+      {{params_.GetDlcAppId(kDlcId), {.name = kDlcId}}});
   FakePrefs fake_prefs;
   FakeSystemState::Get()->set_prefs(&fake_prefs);
   OmahaEvent event(OmahaEvent::kTypeUpdateDownloadStarted);
-  OmahaRequestBuilderXml omaha_request{
-      &event, &omaha_request_params, false, false, 0, 0, 0, &fake_prefs, ""};
+  OmahaRequestBuilderXml omaha_request{&event, false, false, 0, 0, 0, ""};
   // DLC App ID Expectations.
   const string dlc_cohort_key = PrefsInterface::CreateSubKey(
       {kDlcPrefsSubDir, kDlcId, kPrefsOmahaCohort});