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

ui/compositor/compositor.cc

 // 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.
 
 #include "ui/compositor/compositor.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <deque>
@@ skipping 479 matching lines @@
 void Compositor::BeginMainFrame(const cc::BeginFrameArgs& args) {
   for (auto& observer : animation_observer_list_)
     observer.OnAnimationStep(args.frame_time);
   if (animation_observer_list_.might_have_observers())
     host_->SetNeedsAnimate();
 }
 
 void Compositor::BeginMainFrameNotExpectedSoon() {
 }
 
+void Compositor::DoShortIdleWork(const cc::BeginFrameArgs& args) {}
+
 static void SendDamagedRectsRecursive(ui::Layer* layer) {
   layer->SendDamagedRects();
   for (auto* child : layer->children())
     SendDamagedRectsRecursive(child);
 }
 
 void Compositor::UpdateLayerTreeHost() {
   if (!root_layer())
     return;
   SendDamagedRectsRecursive(root_layer());
@@ skipping 66 matching lines @@
   for (auto& observer : observer_list_)
     observer.OnCompositingLockStateChanged(this);
 }
 
 void Compositor::CancelCompositorLock() {
   if (compositor_lock_)
     compositor_lock_->CancelLock();
 }
 
 }  // namespace ui