Removing GL context rate limiting feature and related wrappers

cc/test/fake_proxy.h

Index: cc/test/fake_proxy.h
diff --git a/cc/test/fake_proxy.h b/cc/test/fake_proxy.h
index b840f33204e3d28be696bc95d7e0177eb1329f48..022643132f50c1c830335f2c0f4e00633f4701e0 100644
--- a/cc/test/fake_proxy.h
+++ b/cc/test/fake_proxy.h
@@ -42,7 +42,6 @@ class FakeProxy : public Proxy {
   bool CommitRequested() const override;
   void Start() override {}
   void Stop() override {}
-  void ForceSerializeOnSwapBuffers() override {}
   bool SupportsImplScrolling() const override;
   bool MainFrameWillHappenForTesting() override;
   void SetChildrenNeedBeginFrames(bool children_need_begin_frames) override {}