Move fallback tick handling to compositor thread

content/renderer/android/synchronous_compositor_output_surface.h

Index: content/renderer/android/synchronous_compositor_output_surface.h
diff --git a/content/renderer/android/synchronous_compositor_output_surface.h b/content/renderer/android/synchronous_compositor_output_surface.h
index 7509460ab7bcbcbe277f0d258c36ea7b56e29dbc..96b547fe89fdd7864aa66782babff28980689a38 100644
--- a/content/renderer/android/synchronous_compositor_output_surface.h
+++ b/content/renderer/android/synchronous_compositor_output_surface.h
@@ -10,6 +10,7 @@
 #include <vector>
 
 #include "base/callback.h"
+#include "base/cancelable_callback.h"
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
@@ -103,6 +104,8 @@ class SynchronousCompositorOutputSurface
                        bool hardware_draw);
   bool CalledOnValidThread() const;
 
+  void FallbackTickFired();
+
   const int routing_id_;
   SynchronousCompositorRegistry* const registry_;  // unowned
   bool registered_;
@@ -117,6 +120,9 @@ class SynchronousCompositorOutputSurface
   bool did_swap_;
   scoped_refptr<FrameSwapMessageQueue> frame_swap_message_queue_;
 
+  base::CancelableClosure fallback_tick_;
+  bool fallback_tick_pending_;
+
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(SynchronousCompositorOutputSurface);