If compositor window already exists, then simply return it rather than complaining. May affect how bug 65194 manifests.

BUG=65194
TEST=Verify against WebGL demos, poster circle content with tab opening and closing, as well as killing of GPU process.

Review URL: http://codereview.chromium.org/5528007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@68362 0039d316-1c4b-4281-b951-d872f2087c98

9 files changed, 22 insertions, 19 deletions

diff --git a/chrome/browser/gpu_process_host.cc b/chrome/browser/gpu_process_host.cc
index d4bb2db..abc8273 100644
--- a/chrome/browser/gpu_process_host.cc
+++ b/chrome/browser/gpu_process_host.cc
@@ -186,8 +186,8 @@ void GpuProcessHost::OnControlMessageReceived(const IPC::Message& message) {
     IPC_MESSAGE_HANDLER(GpuHostMsg_AcceleratedSurfaceBuffersSwapped,
                         OnAcceleratedSurfaceBuffersSwapped)
 #elif defined(OS_WIN)
-    IPC_MESSAGE_HANDLER_DELAY_REPLY(GpuHostMsg_CreateCompositorHostWindow,
-                                    OnCreateCompositorHostWindow)
+    IPC_MESSAGE_HANDLER_DELAY_REPLY(GpuHostMsg_GetCompositorHostWindow,
+                                    OnGetCompositorHostWindow)
 #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
@@ -398,14 +398,14 @@ void SendDelayedReply(IPC::Message* reply_msg) {
   GpuProcessHost::Get()->Send(reply_msg);
 }
 
-void CreateCompositorHostWindowDispatcher(
+void GetCompositorHostWindowDispatcher(
     int renderer_id,
     int render_view_id,
     IPC::Message* reply_msg) {
   RenderViewHost* host = RenderViewHost::FromID(renderer_id,
                                                 render_view_id);
   if (!host) {
-    GpuHostMsg_CreateCompositorHostWindow::WriteReplyParams(reply_msg,
+    GpuHostMsg_GetCompositorHostWindow::WriteReplyParams(reply_msg,
         gfx::kNullPluginWindow);
     BrowserThread::PostTask(
       BrowserThread::IO, FROM_HERE,
@@ -414,10 +414,10 @@ void CreateCompositorHostWindowDispatcher(
   }
 
   RenderWidgetHostView* view = host->view();
-  gfx::PluginWindowHandle id = view->CreateCompositorHostWindow();
+  gfx::PluginWindowHandle id = view->GetCompositorHostWindow();
 
 
-  GpuHostMsg_CreateCompositorHostWindow::WriteReplyParams(reply_msg, id);
+  GpuHostMsg_GetCompositorHostWindow::WriteReplyParams(reply_msg, id);
   BrowserThread::PostTask(
     BrowserThread::IO, FROM_HERE,
     NewRunnableFunction(&SendDelayedReply, reply_msg));
@@ -425,13 +425,13 @@ void CreateCompositorHostWindowDispatcher(
 
 }  // namespace
 
-void GpuProcessHost::OnCreateCompositorHostWindow(
+void GpuProcessHost::OnGetCompositorHostWindow(
     int renderer_id,
     int render_view_id,
     IPC::Message* reply_message) {
   BrowserThread::PostTask(
       BrowserThread::UI, FROM_HERE,
-      NewRunnableFunction(&CreateCompositorHostWindowDispatcher,
+      NewRunnableFunction(&GetCompositorHostWindowDispatcher,
           renderer_id, render_view_id, reply_message));
 }
 
diff --git a/chrome/browser/gpu_process_host.h b/chrome/browser/gpu_process_host.h
index 05ae39e..6d8fc9d 100644
--- a/chrome/browser/gpu_process_host.h
+++ b/chrome/browser/gpu_process_host.h
@@ -95,7 +95,7 @@ class GpuProcessHost : public BrowserChildProcessHost, public NonThreadSafe {
   void OnAcceleratedSurfaceBuffersSwapped(
       const GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params& params);
 #elif defined(OS_WIN)
-  void OnCreateCompositorHostWindow(int renderer_id,
+  void OnGetCompositorHostWindow(int renderer_id,
                                     int render_view_id,
                                     IPC::Message* reply_message);
 #endif
diff --git a/chrome/browser/renderer_host/render_widget_host_view.h b/chrome/browser/renderer_host/render_widget_host_view.h
index 8235ebf..81de506 100644
--- a/chrome/browser/renderer_host/render_widget_host_view.h
+++ b/chrome/browser/renderer_host/render_widget_host_view.h
@@ -247,7 +247,7 @@ class RenderWidgetHostView {
 #endif
 
 #if defined(OS_WIN)
-  virtual gfx::PluginWindowHandle CreateCompositorHostWindow() = 0;
+  virtual gfx::PluginWindowHandle GetCompositorHostWindow() = 0;
   virtual void WillWmDestroy() = 0;
   virtual void ShowCompositorHostWindow(bool show) = 0;
 #endif
@@ -261,7 +261,7 @@ class RenderWidgetHostView {
   }
   WebKit::WebPopupType popup_type() const { return popup_type_; }
 
-  // Subclasses should override this method to do whatever is appropriate to set
+  // Subclasses should override this method to do  is appropriate to set
   // the custom background for their platform.
   virtual void SetBackground(const SkBitmap& background) {
     background_ = background;
diff --git a/chrome/browser/renderer_host/render_widget_host_view_win.cc b/chrome/browser/renderer_host/render_widget_host_view_win.cc
index 346045d..f41badf 100644
--- a/chrome/browser/renderer_host/render_widget_host_view_win.cc
+++ b/chrome/browser/renderer_host/render_widget_host_view_win.cc
@@ -1533,8 +1533,11 @@ static LRESULT CALLBACK CompositorHostWindowProc(HWND hWnd, UINT message,
 // Creates a HWND within the RenderWidgetHostView that will serve as a host
 // for a HWND that the GPU process will create. The host window is used
 // to Z-position the GPU's window relative to other plugin windows.
-gfx::PluginWindowHandle RenderWidgetHostViewWin::CreateCompositorHostWindow() {
-  DCHECK(!compositor_host_window_);
+gfx::PluginWindowHandle RenderWidgetHostViewWin::GetCompositorHostWindow() {
+  // If the window has been created, don't recreate it a second time
+  if (compositor_host_window_)
+    return compositor_host_window_;
+
   static ATOM window_class = 0;
   if (!window_class) {
     WNDCLASSEX wcex;
diff --git a/chrome/browser/renderer_host/render_widget_host_view_win.h b/chrome/browser/renderer_host/render_widget_host_view_win.h
index 1195a0c..b2b7546 100644
--- a/chrome/browser/renderer_host/render_widget_host_view_win.h
+++ b/chrome/browser/renderer_host/render_widget_host_view_win.h
@@ -158,7 +158,7 @@ class RenderWidgetHostViewWin
   virtual bool ContainsNativeView(gfx::NativeView native_view) const;
   virtual void SetVisuallyDeemphasized(bool deemphasized);
 
-  virtual gfx::PluginWindowHandle CreateCompositorHostWindow();
+  virtual gfx::PluginWindowHandle GetCompositorHostWindow();
   virtual void ShowCompositorHostWindow(bool show);
 
   virtual void OnAccessibilityNotifications(
diff --git a/chrome/browser/renderer_host/test/test_render_view_host.cc b/chrome/browser/renderer_host/test/test_render_view_host.cc
index c12b942..72674497 100644
--- a/chrome/browser/renderer_host/test/test_render_view_host.cc
+++ b/chrome/browser/renderer_host/test/test_render_view_host.cc
@@ -188,7 +188,7 @@ void TestRenderWidgetHostView::AcceleratedSurfaceBuffersSwapped(
 void TestRenderWidgetHostView::GpuRenderingStateDidChange() {
 }
 #elif defined(OS_WIN)
-gfx::PluginWindowHandle TestRenderWidgetHostView::CreateCompositorHostWindow() {
+gfx::PluginWindowHandle TestRenderWidgetHostView::GetCompositorHostWindow() {
   return gfx::kNullPluginWindow;
 }
 
diff --git a/chrome/browser/renderer_host/test/test_render_view_host.h b/chrome/browser/renderer_host/test/test_render_view_host.h
index b8020c7..01ed8e4 100644
--- a/chrome/browser/renderer_host/test/test_render_view_host.h
+++ b/chrome/browser/renderer_host/test/test_render_view_host.h
@@ -126,7 +126,7 @@ class TestRenderWidgetHostView : public RenderWidgetHostView {
       uint64 swap_buffers_count);
   virtual void GpuRenderingStateDidChange();
 #elif defined(OS_WIN)
-  virtual gfx::PluginWindowHandle CreateCompositorHostWindow();
+  virtual gfx::PluginWindowHandle GetCompositorHostWindow();
   virtual void WillWmDestroy();
   virtual void ShowCompositorHostWindow(bool show);
 #endif
diff --git a/chrome/common/gpu_messages_internal.h b/chrome/common/gpu_messages_internal.h
index 6ad6449..e4badaa 100644
--- a/chrome/common/gpu_messages_internal.h
+++ b/chrome/common/gpu_messages_internal.h
@@ -119,8 +119,8 @@ IPC_BEGIN_MESSAGES(GpuHost)
   IPC_MESSAGE_CONTROL1(GpuHostMsg_AcceleratedSurfaceBuffersSwapped,
                        GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params)
 #elif defined(OS_WIN)
-  // Create and get the HWND for the compositor window
-  IPC_SYNC_MESSAGE_CONTROL2_1(GpuHostMsg_CreateCompositorHostWindow,
+  // Get the HWND for the compositor window and if necessary, create it
+  IPC_SYNC_MESSAGE_CONTROL2_1(GpuHostMsg_GetCompositorHostWindow,
                               int32, /* renderer_id */
                               int32, /* render_view_id */
                               gfx::PluginWindowHandle /* compositor_host_id */)
diff --git a/chrome/gpu/gpu_command_buffer_stub.cc b/chrome/gpu/gpu_command_buffer_stub.cc
index f11308d..6ad18bc 100644
--- a/chrome/gpu/gpu_command_buffer_stub.cc
+++ b/chrome/gpu/gpu_command_buffer_stub.cc
@@ -83,7 +83,7 @@ bool GpuCommandBufferStub::CreateCompositorWindow() {
   // Ask the browser to create the the host window.
   ChildThread* gpu_thread = ChildThread::current();
   gfx::PluginWindowHandle host_window_id = gfx::kNullPluginWindow;
-  gpu_thread->Send(new GpuHostMsg_CreateCompositorHostWindow(
+  gpu_thread->Send(new GpuHostMsg_GetCompositorHostWindow(
       renderer_id_,
       render_view_id_,
       &host_window_id));