Create a new action triggered when a BeginMainFrame is not expected before vsync

ui/compositor/compositor.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_COMPOSITOR_COMPOSITOR_H_
 #define UI_COMPOSITOR_COMPOSITOR_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 335 matching lines @@
   void OnSwapBuffersComplete();
 
   // Signals swap has aborted (e.g. lost context).
   void OnSwapBuffersAborted();
 
   // LayerTreeHostClient implementation.
   void WillBeginMainFrame() override {}
   void DidBeginMainFrame() override {}
   void BeginMainFrame(const cc::BeginFrameArgs& args) override;
   void BeginMainFrameNotExpectedSoon() override;
+  void DoShortIdleWork(const cc::BeginFrameArgs& args) override;
   void UpdateLayerTreeHost() override;
   void ApplyViewportDeltas(const gfx::Vector2dF& inner_delta,
                            const gfx::Vector2dF& outer_delta,
                            const gfx::Vector2dF& elastic_overscroll_delta,
                            float page_scale,
                            float top_controls_delta) override {}
   void RequestNewCompositorFrameSink() override;
   void DidInitializeCompositorFrameSink() override {}
   void DidFailToInitializeCompositorFrameSink() override;
   void WillCommit() override {}
@@ skipping 78 matching lines @@
   gfx::ColorSpace blending_color_space_;
 
   base::WeakPtrFactory<Compositor> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(Compositor);
 };
 
 }  // namespace ui
 
 #endif  // UI_COMPOSITOR_COMPOSITOR_H_