Make GPU back-pressure work with remote CALayers

content/browser/compositor/browser_compositor_view_private_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 "content/browser/compositor/browser_compositor_view_private_mac.h"
 
 #include <map>
 
 #include "base/debug/trace_event.h"
 #include "base/lazy_instance.h"
@@ skipping 73 matching lines @@
 }
 
 void BrowserCompositorViewMacInternal::ResetClient() {
   if (!client_)
     return;
 
   // Disable the fade-out animation as the view is removed.
   ScopedCAActionDisabler disabler;
 
   [flipped_layer_ removeFromSuperlayer];
+  DestroyIOSurfaceLayer(io_surface_layer_);
+  DestroyCAContextLayer(ca_context_layer_);
+  DestroySoftwareLayer();
 
-  [io_surface_layer_ removeFromSuperlayer];
-  [io_surface_layer_ resetClient];
-  io_surface_layer_.reset();
   accelerated_output_surface_id_ = 0;
-
-  [software_layer_ removeFromSuperlayer];
-  software_layer_.reset();
-
   last_swap_size_dip_ = gfx::Size();
 
   compositor_->SetScaleAndSize(1.0, gfx::Size(0, 0));
   compositor_->SetRootLayer(NULL);
   client_ = NULL;
 }
 
 bool BrowserCompositorViewMacInternal::HasFrameOfSize(
     const gfx::Size& dip_size) const {
   return last_swap_size_dip_ == dip_size;
 }
 
+int BrowserCompositorViewMacInternal::GetRendererID() const {
+  if (io_surface_layer_)
+    return [io_surface_layer_ iosurface]->GetRendererID();
+  return 0;
+}
+
 void BrowserCompositorViewMacInternal::BeginPumpingFrames() {
   [io_surface_layer_ beginPumpingFrames];
 }
 
 void BrowserCompositorViewMacInternal::EndPumpingFrames() {
   [io_surface_layer_ endPumpingFrames];
 }
 
 void BrowserCompositorViewMacInternal::GotAcceleratedFrame(
     uint64 surface_handle, int output_surface_id,
@@ skipping 242 matching lines @@
       g_widget_to_internals_map.Pointer()->find(widget);
   // This can end up being accessed after the underlying widget has been
   // destroyed, but while the ui::Compositor is still being destroyed.
   // Return NULL in these cases.
   if (found == g_widget_to_internals_map.Pointer()->end())
     return NULL;
   return found->second;
 }
 
 }  // namespace content