Use inner HWND for accelerated rendering on windows

chrome/browser/gpu_process_host.cc

Index: chrome/browser/gpu_process_host.cc
===================================================================
--- chrome/browser/gpu_process_host.cc	(revision 66779)
+++ chrome/browser/gpu_process_host.cc	(working copy)
@@ -202,6 +202,10 @@
                         OnAcceleratedSurfaceSetIOSurface)
     IPC_MESSAGE_HANDLER(GpuHostMsg_AcceleratedSurfaceBuffersSwapped,
                         OnAcceleratedSurfaceBuffersSwapped)
+#elif defined(OS_WIN)
+    IPC_MESSAGE_HANDLER_DELAY_REPLY(GpuHostMsg_CreateCompositorHostWindow,
+                                    OnCreateCompositorHostWindow)
+    IPC_MESSAGE_HANDLER(GpuHostMsg_ScheduleComposite, OnScheduleComposite)
 #endif
     // If the IO thread does not handle the message then automatically route it
     // to the UI thread. The UI thread will report an error if it does not
@@ -347,6 +351,58 @@
       new BuffersSwappedDispatcher(
           renderer_id, render_view_id, window, surface_id));
 }
+
+#elif defined(OS_WIN)
+
+namespace {
+
+void SendDelayedReply(IPC::Message* reply_msg) {
+  GpuProcessHost::Get()->Send(reply_msg);
+}
+
+void CreateCompositorHostWindowDispatcher(
+    int renderer_id,
+    int render_view_id,
+    IPC::Message* reply_msg) {
+  RenderViewHost* host = RenderViewHost::FromID(renderer_id,

[apatrick_chromium, 2010/11/19 23:09:51]

What if the renderer process has been destroyed or has crashed. Won't this
return null?

[nduca, 2010/11/20 00:28:49]

Done.

+                                                render_view_id);
+
+  RenderWidgetHostView* view = host->view();
+  gfx::PluginWindowHandle id = view->CreateCompositorHostWindow();
+
+
+  GpuHostMsg_CreateCompositorHostWindow::WriteReplyParams(reply_msg, id);
+  BrowserThread::PostTask(

[apatrick_chromium, 2010/11/19 23:09:51]

If this is running on the UI thread it should be in GpuProcessHostUIShim and it
should call GpuProcessHostUIShim::Send(reply_msg). The code in this file all
runs on the IO thread. That wan't the case until recently. You might need to
sync to see the fixes I made.

[nduca, 2010/11/20 00:28:49]

Summarizing verbal conversation: the reason that this approach works here is
that this function isn't mutating any of the host parameters.

On 2010/11/19 23:09:51, apatrick_chromium wrote:

+    BrowserThread::IO, FROM_HERE,
+    NewRunnableFunction(&SendDelayedReply, reply_msg));
+}
+
+void ScheduleCompositeDispatcher(int renderer_id, int render_view_id) {
+  RenderViewHost* host = RenderViewHost::FromID(renderer_id,
+                                                render_view_id);
+  DCHECK(host);

[apatrick_chromium, 2010/11/19 23:09:51]

See above about renderer process terminating.

[nduca, 2010/11/20 00:28:49]

Done.

+
+
+  host->ScheduleComposite();
+}
+}  // namespace
+
+void GpuProcessHost::OnCreateCompositorHostWindow(
+    int32 renderer_id,
+    int32 render_view_id,
+    IPC::Message* reply_message) {
+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      NewRunnableFunction(&CreateCompositorHostWindowDispatcher,
+          renderer_id, render_view_id, reply_message));
+}
+
+void GpuProcessHost::OnScheduleComposite(int renderer_id, int render_view_id) {

[apatrick_chromium, 2010/11/19 23:09:51]

Messages received by GpuProcessHost but not handled are automatically posted to
GpuProcessHostUIShim on the UI thread. That won't work for messages that expect
a reply though I think so OnCreateCompositorHostWindow will probably have to
stay as is.

[nduca, 2010/11/20 00:28:49]

Done.

+  BrowserThread::PostTask(
+      BrowserThread::UI, FROM_HERE,
+      NewRunnableFunction(&ScheduleCompositeDispatcher,
+          renderer_id, render_view_id));
+}
 #endif
 
 void GpuProcessHost::SendEstablishChannelReply(