Update from https://crrev.com/312600

cc/trees/thread_proxy.h

Index: cc/trees/thread_proxy.h
diff --git a/cc/trees/thread_proxy.h b/cc/trees/thread_proxy.h
index f8808f90870e41c9ef4c46ce1e146a9804712cbd..0d15b5a67f2408b7a6673649300d6aeb1a72d40e 100644
--- a/cc/trees/thread_proxy.h
+++ b/cc/trees/thread_proxy.h
@@ -209,6 +209,7 @@ class CC_EXPORT ThreadProxy : public Proxy,
                                             base::TimeDelta delay) override;
   void DidActivateSyncTree() override;
   void DidPrepareTiles() override;
+  void DidCompletePageScaleAnimationOnImplThread() override;
 
   // SchedulerClient implementation
   void WillBeginImplFrame(const BeginFrameArgs& args) override;
@@ -251,6 +252,7 @@ class CC_EXPORT ThreadProxy : public Proxy,
   void DidInitializeOutputSurface(bool success,
                                   const RendererCapabilities& capabilities);
   void SendCommitRequestToImplThreadIfNeeded();
+  void DidCompletePageScaleAnimation();
 
   // Called on impl thread.
   struct SchedulerStateRequest;