Mac Overlays: Add GPU back-pressure

ui/accelerated_widget_mac/accelerated_widget_mac.mm

 // 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 "ui/accelerated_widget_mac/accelerated_widget_mac.h"
 
 #include <map>
 
 #include "base/lazy_instance.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 92 matching lines @@
     const gfx::Size& dip_size) const {
   return last_swap_size_dip_ == dip_size;
 }
 
 int AcceleratedWidgetMac::GetRendererID() const {
   if (io_surface_layer_)
     return [io_surface_layer_ rendererID];
   return 0;
 }
 
+uint32_t AcceleratedWidgetMac::GetDisplayIDForVSync() const {
+  if (view_)
+    return view_->AcceleratedWidgetGetDisplayIDForVSync();
+  return 0;
+}
+
 bool AcceleratedWidgetMac::IsRendererThrottlingDisabled() const {
   if (view_)
     return view_->AcceleratedWidgetShouldIgnoreBackpressure();
   return false;
 }
 
 void AcceleratedWidgetMac::BeginPumpingFrames() {
   [io_surface_layer_ beginPumpingFrames];
 }
 
@@ skipping 235 matching lines @@
     view_->AcceleratedWidgetHitError();
 }
 
 void AcceleratedWidgetMacGotAcceleratedFrame(
     gfx::AcceleratedWidget widget, uint64 surface_handle,
     const std::vector<ui::LatencyInfo>& latency_info,
     const gfx::Size& pixel_size,
     float scale_factor,
     const gfx::Rect& pixel_damage_rect,
     const base::Closure& drawn_callback,
-    bool* disable_throttling, int* renderer_id) {
+    bool* disable_throttling, int* renderer_id, uint32_t* display_id) {
   AcceleratedWidgetMac* accelerated_widget_mac =
       GetHelperFromAcceleratedWidget(widget);
   if (accelerated_widget_mac) {
     accelerated_widget_mac->GotAcceleratedFrame(
         surface_handle, latency_info, pixel_size, scale_factor,
         pixel_damage_rect, drawn_callback);
     *disable_throttling =
         accelerated_widget_mac->IsRendererThrottlingDisabled();
     *renderer_id = accelerated_widget_mac->GetRendererID();
+    *display_id = accelerated_widget_mac->GetDisplayIDForVSync();
   } else {
     *disable_throttling = false;
     *renderer_id = 0;
+    *display_id = 0;
   }
 }
 
 void AcceleratedWidgetMacGotSoftwareFrame(
     gfx::AcceleratedWidget widget, float scale_factor, SkCanvas* canvas) {
   AcceleratedWidgetMac* accelerated_widget_mac =
       GetHelperFromAcceleratedWidget(widget);
   if (accelerated_widget_mac)
     accelerated_widget_mac->GotSoftwareFrame(scale_factor, canvas);
 }
 
 }  // namespace ui