Convert FieldTrialActivated to use mojo.

chrome/renderer/chrome_render_thread_observer.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/chrome_render_thread_observer.h"
 
 #include <stddef.h>
 
 #include <limits>
 #include <memory>
@@ skipping 28 matching lines @@
 #include "chrome/renderer/security_filter_peer.h"
 #include "components/visitedlink/renderer/visitedlink_slave.h"
 #include "content/public/child/resource_dispatcher_delegate.h"
 #include "content/public/renderer/render_thread.h"
 #include "content/public/renderer/render_view.h"
 #include "content/public/renderer/render_view_visitor.h"
 #include "media/base/media_resources.h"
 #include "mojo/public/cpp/bindings/strong_binding.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_module.h"
+#include "services/service_manager/public/cpp/interface_provider.h"
 #include "services/service_manager/public/cpp/interface_registry.h"
 #include "third_party/WebKit/public/web/WebCache.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebFrame.h"
 #include "third_party/WebKit/public/web/WebSecurityPolicy.h"
 #include "third_party/WebKit/public/web/WebView.h"
 
 #if defined(ENABLE_EXTENSIONS)
 #include "chrome/renderer/extensions/extension_localization_peer.h"
 #endif
@@ skipping 226 matching lines @@
   return handled;
 }
 
 void ChromeRenderThreadObserver::OnRenderProcessShutdown() {
   visited_link_slave_.reset();
 }
 
 void ChromeRenderThreadObserver::OnFieldTrialGroupFinalized(
     const std::string& trial_name,
     const std::string& group_name) {
-  content::RenderThread::Get()->Send(
-      new ChromeViewHostMsg_FieldTrialActivated(trial_name));
+  if (!field_trial_recorder_)

[Sam McNally, 2016/11/07 06:56:54]

OnFieldTrialGroupFinalized seems like it should only be called once per process,
so |field_trial_recorder_| can just be a local. Otherwise, resetting
|field_trial_recorder_| in OnRenderProcessShutdown() above should fix your
single-process test threading issues.

[nigeltao1, 2016/11/10 06:23:04]

I made it a local.

+    content::RenderThread::Get()->GetRemoteInterfaces()->GetInterface(
+        &field_trial_recorder_);
+  field_trial_recorder_->FieldTrialActivated(trial_name);
 }
 
 void ChromeRenderThreadObserver::OnSetIsIncognitoProcess(
     bool is_incognito_process) {
   is_incognito_process_ = is_incognito_process;
 }
 
 void ChromeRenderThreadObserver::OnSetContentSettingRules(
     const RendererContentSettingRules& rules) {
   content_setting_rules_ = rules;
 }
 
 void ChromeRenderThreadObserver::OnSetFieldTrialGroup(
     const std::string& trial_name,
     const std::string& group_name) {
   field_trial_syncer_.OnSetFieldTrialGroup(trial_name, group_name);
 }
 
 const RendererContentSettingRules*
 ChromeRenderThreadObserver::content_setting_rules() const {
   return &content_setting_rules_;
 }