update_engine: Use org.chromium.NetworkProxyService.

Make update_engine call Chrome's new
org.chromium.NetworkProxyService D-Bus service to resolve
network proxies instead of using
org.chromium.LibCrosService. The new service supports
asynchronous replies instead of responding via D-Bus
signals.

BUG=chromium:446115,chromium:703217
TEST=unit tests pass; also added debug logging and verified
     that chrome's proxy settings are used

Change-Id: Iebd268ea3e551c0760416d955828b9d7ebf851fb
Reviewed-on: https://chromium-review.googlesource.com/497491
Commit-Ready: Dan Erat <derat@chromium.org>
Tested-by: Dan Erat <derat@chromium.org>
Reviewed-by: Ben Chan <benchan@chromium.org>
diff --git a/update_attempter.h b/update_attempter.h
index c0c4d79..d354f40 100644
--- a/update_attempter.h
+++ b/update_attempter.h
@@ -29,13 +29,11 @@
 #include <base/time/time.h>
 #include <gtest/gtest_prod.h>  // for FRIEND_TEST
 
-#include "debugd/dbus-proxies.h"
 #include "update_engine/chrome_browser_proxy_resolver.h"
 #include "update_engine/client_library/include/update_engine/update_status.h"
 #include "update_engine/common/action_processor.h"
 #include "update_engine/common/certificate_checker.h"
 #include "update_engine/common/cpu_limiter.h"
-#include "update_engine/libcros_proxy.h"
 #include "update_engine/omaha_request_params.h"
 #include "update_engine/omaha_response_handler_action.h"
 #include "update_engine/payload_consumer/download_action.h"
@@ -49,6 +47,13 @@
 
 class MetricsLibraryInterface;
 
+namespace org {
+namespace chromium {
+class debugdProxyInterface;
+class NetworkProxyServiceInterfaceProxyInterface;
+}  // namespace chromium
+}  // namespace org
+
 namespace policy {
 class PolicyProvider;
 }
@@ -68,7 +73,8 @@
 
   UpdateAttempter(SystemState* system_state,
                   CertificateChecker* cert_checker,
-                  LibCrosProxy* libcros_proxy,
+                  org::chromium::NetworkProxyServiceInterfaceProxyInterface*
+                      network_proxy_service_proxy,
                   org::chromium::debugdProxyInterface* debugd_proxy);
   ~UpdateAttempter() override;