Convert ChromeViewMsg_SetFieldTrialGroup to use mojo.

chrome/renderer/chrome_render_thread_observer.cc

Index: chrome/renderer/chrome_render_thread_observer.cc
diff --git a/chrome/renderer/chrome_render_thread_observer.cc b/chrome/renderer/chrome_render_thread_observer.cc
index 996518506ab0188bad786eda5dea084785c04030..9c8f98294dc98f990b04cd25b75dcbc1d4516f78 100644
--- a/chrome/renderer/chrome_render_thread_observer.cc
+++ b/chrome/renderer/chrome_render_thread_observer.cc
@@ -30,7 +30,7 @@
 #include "build/build_config.h"
 #include "chrome/common/child_process_logging.h"
 #include "chrome/common/chrome_paths.h"
-#include "chrome/common/field_trial_recorder.mojom.h"
+#include "chrome/common/field_trial.mojom.h"
 #include "chrome/common/media/media_resource_provider.h"
 #include "chrome/common/net/net_resource_provider.h"
 #include "chrome/common/render_messages.h"
@@ -278,6 +278,9 @@ ChromeRenderThreadObserver::~ChromeRenderThreadObserver() {}
 void ChromeRenderThreadObserver::RegisterMojoInterfaces(
     content::AssociatedInterfaceRegistry* associated_interfaces) {
   associated_interfaces->AddInterface(base::Bind(
+      &ChromeRenderThreadObserver::OnFieldTrialGroupSetterAssociatedRequest,
+      base::Unretained(this)));
+  associated_interfaces->AddInterface(base::Bind(
       &ChromeRenderThreadObserver::OnRendererConfigurationAssociatedRequest,
       base::Unretained(this)));
 }
@@ -285,23 +288,16 @@ void ChromeRenderThreadObserver::RegisterMojoInterfaces(
 void ChromeRenderThreadObserver::UnregisterMojoInterfaces(
     content::AssociatedInterfaceRegistry* associated_interfaces) {
   associated_interfaces->RemoveInterface(
+      chrome::mojom::FieldTrialGroupSetter::Name_);
+  associated_interfaces->RemoveInterface(
       chrome::mojom::RendererConfiguration::Name_);
 }
 
-bool ChromeRenderThreadObserver::OnControlMessageReceived(
-    const IPC::Message& message) {
-  bool handled = true;
-  IPC_BEGIN_MESSAGE_MAP(ChromeRenderThreadObserver, message)
-    IPC_MESSAGE_HANDLER(ChromeViewMsg_SetFieldTrialGroup, OnSetFieldTrialGroup)
-    IPC_MESSAGE_UNHANDLED(handled = false)
-  IPC_END_MESSAGE_MAP()
-  return handled;
-}
-
 void ChromeRenderThreadObserver::OnRenderProcessShutdown() {
   visited_link_slave_.reset();
 
   // Workaround for http://crbug.com/672646
+  field_trial_group_setter_bindings_.CloseAllBindings();
   renderer_configuration_bindings_.CloseAllBindings();
 }
 
@@ -314,6 +310,12 @@ void ChromeRenderThreadObserver::OnFieldTrialGroupFinalized(
   field_trial_recorder->FieldTrialActivated(trial_name);
 }
 
+void ChromeRenderThreadObserver::SetFieldTrialGroup(
+    const std::string& trial_name,
+    const std::string& group_name) {
+  field_trial_syncer_.OnSetFieldTrialGroup(trial_name, group_name);
+}
+
 void ChromeRenderThreadObserver::SetInitialConfiguration(
     bool is_incognito_process) {
   is_incognito_process_ = is_incognito_process;
@@ -324,17 +326,16 @@ void ChromeRenderThreadObserver::SetContentSettingRules(
   content_setting_rules_ = rules;
 }
 
+void ChromeRenderThreadObserver::OnFieldTrialGroupSetterAssociatedRequest(
+    chrome::mojom::FieldTrialGroupSetterAssociatedRequest request) {
+  field_trial_group_setter_bindings_.AddBinding(this, std::move(request));
+}
+
 void ChromeRenderThreadObserver::OnRendererConfigurationAssociatedRequest(
     chrome::mojom::RendererConfigurationAssociatedRequest request) {
   renderer_configuration_bindings_.AddBinding(this, std::move(request));
 }
 
-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_;