WIP - Gutterless resize on Windows

content/browser/gpu/browser_gpu_channel_host_factory.cc

Index: content/browser/gpu/browser_gpu_channel_host_factory.cc
diff --git a/content/browser/gpu/browser_gpu_channel_host_factory.cc b/content/browser/gpu/browser_gpu_channel_host_factory.cc
index 3a385ca6a46dd01f11a5e17b6d92d5f0c9057671..4aa13dc13b243edc37d7b5512e475306de5646cd 100644
--- a/content/browser/gpu/browser_gpu_channel_host_factory.cc
+++ b/content/browser/gpu/browser_gpu_channel_host_factory.cc
@@ -28,6 +28,7 @@
 #include "gpu/command_buffer/service/gpu_switches.h"
 #include "ipc/ipc_channel_handle.h"
 #include "ipc/message_filter.h"
+#include "ui/base/window_resize_helper.h"
 
 namespace content {
 
@@ -344,6 +345,18 @@ CreateCommandBufferResult BrowserGpuChannelHostFactory::CreateViewCommandBuffer(
   return request.result;
 }
 
+scoped_refptr<base::SingleThreadTaskRunner>
+BrowserGpuChannelHostFactory::TaskRunner() {
+#if defined(OS_MACOSX) || defined(OS_WIN)
+  // If we're adding a route to the main UI thread, we need to use the
+  // WindowResizeHelper's task runner, otherwise Gpu Channel messages will be
+  // blocked during a resize and we won't recieve the swap complete signal.
+  return ui::WindowResizeHelper::Get()->task_runner();
+#else
+  return base::ThreadTaskRunnerHandle::Get();
+#endif
+}
+
 // Blocking the UI thread to open a GPU channel is not supported on Android.
 // (Opening the initial channel to a child process involves handling a reply
 // task on the UI thread first, so we cannot block here.)