Automatically redraw the display on resume.

services/surfaces/surfaces_scheduler.cc

 // Copyright 2014 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 "services/surfaces/surfaces_scheduler.h"
 
 #include "cc/surfaces/display.h"
 
 namespace surfaces {
 
@@ skipping 19 matching lines @@
 }
 
 void SurfacesScheduler::OnVSyncParametersUpdated(base::TimeTicks timebase,
                                                  base::TimeDelta interval) {
   scheduler_->CommitVSyncParameters(timebase, interval);
 }
 
 void SurfacesScheduler::AddDisplay(cc::Display* display) {
   DCHECK(displays_.find(display) == displays_.end());
   displays_.insert(display);
+
+  // A draw might be necessary (e.g., this display might be getting added on
+  // resumption from backgrounding).
+  SetNeedsDraw();
 }
 
 void SurfacesScheduler::RemoveDisplay(cc::Display* display) {
   auto it = displays_.find(display);
   DCHECK(it != displays_.end());
   displays_.erase(it);
 }
 
 void SurfacesScheduler::WillBeginImplFrame(const cc::BeginFrameArgs& args) {
 }
@@ skipping 54 matching lines @@
 }
 
 void SurfacesScheduler::SendBeginFramesToChildren(
     const cc::BeginFrameArgs& args) {
 }
 
 void SurfacesScheduler::SendBeginMainFrameNotExpectedSoon() {
 }
 
 }  // namespace mojo