Enable BeginFrame scheduling on aura

content/browser/compositor/browser_compositor_output_surface.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 "content/browser/compositor/browser_compositor_output_surface.h"
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/location.h"
 #include "base/strings/string_number_conversions.h"
+#include "cc/base/switches.h"
 #include "content/browser/compositor/browser_compositor_overlay_candidate_validator.h"
 #include "content/browser/compositor/reflector_impl.h"
 #include "content/common/gpu/client/context_provider_command_buffer.h"
 
 namespace content {
 
 BrowserCompositorOutputSurface::BrowserCompositorOutputSurface(
     const scoped_refptr<cc::ContextProvider>& context_provider,
     const scoped_refptr<ui::CompositorVSyncManager>& vsync_manager,
     scoped_ptr<BrowserCompositorOverlayCandidateValidator>
         overlay_candidate_validator)
     : OutputSurface(context_provider),
       vsync_manager_(vsync_manager),
-      reflector_(nullptr) {
+      reflector_(nullptr),
+      use_begin_frame_scheduling_(base::CommandLine::ForCurrentProcess()->
+          HasSwitch(cc::switches::kEnableBeginFrameScheduling)) {
   overlay_candidate_validator_ = overlay_candidate_validator.Pass();
   Initialize();
 }
 
 BrowserCompositorOutputSurface::BrowserCompositorOutputSurface(
     scoped_ptr<cc::SoftwareOutputDevice> software_device,
     const scoped_refptr<ui::CompositorVSyncManager>& vsync_manager)
     : OutputSurface(software_device.Pass()),
       vsync_manager_(vsync_manager),
-      reflector_(nullptr) {
+      reflector_(nullptr),
+      use_begin_frame_scheduling_(base::CommandLine::ForCurrentProcess()->
+          HasSwitch(cc::switches::kEnableBeginFrameScheduling)) {
   Initialize();
 }
 
 BrowserCompositorOutputSurface::~BrowserCompositorOutputSurface() {
   if (reflector_)
     reflector_->DetachFromOutputSurface();
   DCHECK(!reflector_);
   if (!HasClient())
     return;
-  vsync_manager_->RemoveObserver(this);
+
+  // When BeginFrame scheduling is enabled, vsync info is not routed to renderer
+  // by using |vsync_manager_|. Instead, BeginFrame message is used.
+  if (!use_begin_frame_scheduling_)
+    vsync_manager_->RemoveObserver(this);
 }
 
 void BrowserCompositorOutputSurface::Initialize() {
   capabilities_.max_frames_pending = 1;
   capabilities_.adjust_deadline_for_parent = false;
 }
 
 bool BrowserCompositorOutputSurface::BindToClient(
     cc::OutputSurfaceClient* client) {
   if (!OutputSurface::BindToClient(client))
     return false;
+
   // Don't want vsync notifications until there is a client.
-  vsync_manager_->AddObserver(this);
+  if (!use_begin_frame_scheduling_)
+    vsync_manager_->AddObserver(this);
   return true;
 }
 
 void BrowserCompositorOutputSurface::OnUpdateVSyncParameters(
     base::TimeTicks timebase,
     base::TimeDelta interval) {
   DCHECK(HasClient());
+  DCHECK(!use_begin_frame_scheduling_);
   CommitVSyncParameters(timebase, interval);
 }
 
 void BrowserCompositorOutputSurface::OnUpdateVSyncParametersFromGpu(
     base::TimeTicks timebase,
     base::TimeDelta interval) {
   DCHECK(HasClient());
+  if (use_begin_frame_scheduling_) {
+    CommitVSyncParameters(timebase, interval);
+    return;
+  }
+
   vsync_manager_->UpdateVSyncParameters(timebase, interval);
 }
 
 void BrowserCompositorOutputSurface::SetReflector(ReflectorImpl* reflector) {
   // Software mirroring is done by doing a GL copy out of the framebuffer - if
   // we have overlays then that data will be missing.
   if (overlay_candidate_validator_) {
     overlay_candidate_validator_->SetSoftwareMirrorMode(reflector != nullptr);
   }
   reflector_ = reflector;
 
   OnReflectorChanged();
 }
 
 void BrowserCompositorOutputSurface::OnReflectorChanged() {
 }
 
 base::Closure
 BrowserCompositorOutputSurface::CreateCompositionStartedCallback() {
   return base::Closure();
 }
 
 cc::OverlayCandidateValidator*
 BrowserCompositorOutputSurface::GetOverlayCandidateValidator() const {
   return overlay_candidate_validator_.get();
 }
 
 }  // namespace content