Move FieldTrialRecorder mojom to content

content/public/test/mock_render_thread.h

Index: content/public/test/mock_render_thread.h
diff --git a/content/public/test/mock_render_thread.h b/content/public/test/mock_render_thread.h
index 67e625df02003d484462b01260cfe8788b808b98..fd534427bd9fe0047107a0f7e1cecb85d8b15eba 100644
--- a/content/public/test/mock_render_thread.h
+++ b/content/public/test/mock_render_thread.h
@@ -90,6 +90,8 @@ class MockRenderThread : public RenderThread {
   ServiceManagerConnection* GetServiceManagerConnection() override;
   service_manager::InterfaceRegistry* GetInterfaceRegistry() override;
   service_manager::InterfaceProvider* GetRemoteInterfaces() override;
+  void SetFieldTrialGroup(const std::string& trial_name,
+                          const std::string& group_name) override;
 
   //////////////////////////////////////////////////////////////////////////
   // The following functions are called by the test itself.