Field trial synchronization to PPAPI process.

content/ppapi_plugin/ppapi_thread.h

Index: content/ppapi_plugin/ppapi_thread.h
diff --git a/content/ppapi_plugin/ppapi_thread.h b/content/ppapi_plugin/ppapi_thread.h
index a3b322bb7aa6a07bca4082174d29f60f9aeb30f4..43bcd398bbf13a8ec71b3a97da6dd9bc44d05e97 100644
--- a/content/ppapi_plugin/ppapi_thread.h
+++ b/content/ppapi_plugin/ppapi_thread.h
@@ -13,9 +13,11 @@
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
+#include "base/metrics/field_trial.h"
 #include "base/process/process.h"
 #include "base/scoped_native_library.h"
 #include "build/build_config.h"
+#include "components/variations/child_process_field_trial_syncer.h"
 #include "content/child/child_thread_impl.h"
 #include "content/public/common/pepper_plugin_info.h"
 #include "ppapi/c/pp_module.h"
@@ -50,7 +52,8 @@ class PpapiBlinkPlatformImpl;
 
 class PpapiThread : public ChildThreadImpl,
                     public ppapi::proxy::PluginDispatcher::PluginDelegate,
-                    public ppapi::proxy::PluginProxyDelegate {
+                    public ppapi::proxy::PluginProxyDelegate,
+                    public base::FieldTrialList::Observer {
  public:
   PpapiThread(const base::CommandLine& command_line, bool is_broker);
   ~PpapiThread() override;
@@ -110,6 +113,10 @@ class PpapiThread : public ChildThreadImpl,
   void OnCrash();
   void OnHang();
 
+  // base::FieldTrialList::Observer:
+  void OnFieldTrialGroupFinalized(const std::string& trial_name,
+                                  const std::string& group_name) override;
+
   // Sets up the channel to the given renderer. If |renderer_pid| is
   // base::kNullProcessId, the channel is set up to the browser. On success,
   // returns true and fills the given ChannelHandle with the information from
@@ -172,6 +179,8 @@ class PpapiThread : public ChildThreadImpl,
   base::win::ScopedHandle peer_handle_;
 #endif
 
+  variations::ChildProcessFieldTrialSyncer field_trial_syncer_;
+
   DISALLOW_IMPLICIT_CONSTRUCTORS(PpapiThread);
 };