Update to use libbrillo Chrome proxy resolver

This uses the new proxy resolution code in libbrillo for doing proxy
resolution rather than making the D-Bus calls directly through the
generated bindings. The unittest for this class was removed since the
main function of it was removed. It now is essentially just a wrapper
around the call into libbrillo along with some minimal code for
allowing cancelling of callbacks.

BUG=chromium:771386
TEST=Unit tests pass

Change-Id: Ib0d4e413482f4bdfe0e9689f68118efbec94ec9d
Reviewed-on: https://chromium-review.googlesource.com/698964
Commit-Ready: Jeffrey Kardatzke <jkardatzke@google.com>
Tested-by: Jeffrey Kardatzke <jkardatzke@google.com>
Reviewed-by: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Jeffrey Kardatzke <jkardatzke@google.com>
Reviewed-by: Sen Jiang <senj@chromium.org>
diff --git a/real_system_state.cc b/real_system_state.cc
index b6e59cd..d1af41f 100644
--- a/real_system_state.cc
+++ b/real_system_state.cc
@@ -24,9 +24,9 @@
 #include <base/memory/ptr_util.h>
 #include <base/time/time.h>
 #include <brillo/message_loops/message_loop.h>
-#if USE_CHROME_KIOSK_APP || USE_CHROME_NETWORK_PROXY
+#if USE_CHROME_KIOSK_APP
 #include <chromeos/dbus/service_constants.h>
-#endif  // USE_CHROME_KIOSK_APP || USE_CHROME_NETWORK_PROXY
+#endif  // USE_CHROME_KIOSK_APP
 
 #include "update_engine/common/boot_control.h"
 #include "update_engine/common/boot_control_stub.h"
@@ -69,12 +69,6 @@
   libcros_proxy_.reset(new org::chromium::LibCrosServiceInterfaceProxy(
       DBusConnection::Get()->GetDBus(), chromeos::kLibCrosServiceName));
 #endif  // USE_CHROME_KIOSK_APP
-#if USE_CHROME_NETWORK_PROXY
-  network_proxy_service_proxy_.reset(
-      new org::chromium::NetworkProxyServiceInterfaceProxy(
-          DBusConnection::Get()->GetDBus(),
-          chromeos::kNetworkProxyServiceName));
-#endif  // USE_CHROME_NETWORK_PROXY
 
   LOG_IF(INFO, !hardware_->IsNormalBootMode()) << "Booted in dev mode.";
   LOG_IF(INFO, !hardware_->IsOfficialBuild()) << "Booted non-official build.";
@@ -145,14 +139,8 @@
       new CertificateChecker(prefs_.get(), &openssl_wrapper_));
   certificate_checker_->Init();
 
-  update_attempter_.reset(
-      new UpdateAttempter(this,
-                          certificate_checker_.get(),
-#if USE_CHROME_NETWORK_PROXY
-                          network_proxy_service_proxy_.get()));
-#else
-                          nullptr));
-#endif  // USE_CHROME_NETWORK_PROXY
+  update_attempter_.reset(new UpdateAttempter(this,
+                                              certificate_checker_.get()));
 
   // Initialize the UpdateAttempter before the UpdateManager.
   update_attempter_->Init();