Clean up GPU back-pressure with remote CALayers

content/browser/compositor/browser_compositor_view_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_mac.h"
 
 #include "base/debug/trace_event.h"
 #include "base/lazy_instance.h"
 #include "content/browser/gpu/gpu_process_host_ui_shim.h"
 #include "content/browser/compositor/browser_compositor_ca_layer_tree_mac.h"
@@ skipping 64 matching lines @@
 
 // static
 void BrowserCompositorViewMac::GotAcceleratedFrame(
     gfx::AcceleratedWidget widget,
     uint64 surface_handle, int surface_id,
     const std::vector<ui::LatencyInfo>& latency_info,
     gfx::Size pixel_size, float scale_factor,
     int gpu_host_id, int gpu_route_id) {
   BrowserCompositorCALayerTreeMac* ca_layer_tree =
       BrowserCompositorCALayerTreeMac::FromAcceleratedWidget(widget);
+  bool disable_throttling = false;
   int renderer_id = 0;
   if (ca_layer_tree) {
     ca_layer_tree->GotAcceleratedFrame(
         surface_handle, surface_id, latency_info, pixel_size, scale_factor);
+    disable_throttling = ca_layer_tree->IsRendererThrottlingDisabled();
     renderer_id = ca_layer_tree->GetRendererID();
   }
 
   // Acknowledge the swap, now that it has been processed.
   AcceleratedSurfaceMsg_BufferPresented_Params ack_params;
+  ack_params.disable_throttling = disable_throttling;
   ack_params.renderer_id = renderer_id;
   GpuProcessHostUIShim* ui_shim = GpuProcessHostUIShim::FromID(gpu_host_id);
   if (ui_shim) {
     ui_shim->Send(new AcceleratedSurfaceMsg_BufferPresented(
         gpu_route_id, ack_params));
   }
 }
 
 // static
 void BrowserCompositorViewMac::GotSoftwareFrame(
@@ skipping 16 matching lines @@
   DCHECK_GT(g_placeholder_count, 0u);
   g_placeholder_count -= 1;
 
   // If there are no placeholders allocated, destroy the recyclable
   // BrowserCompositorCALayerTreeMac.
   if (!g_placeholder_count)
     g_recyclable_ca_layer_tree.Get().reset();
 }
 
 }  // namespace content