Fix the mac hangup when force-compositing-mode is enabled

content/common/gpu/gpu_command_buffer_stub.cc

Index: content/common/gpu/gpu_command_buffer_stub.cc
diff --git a/content/common/gpu/gpu_command_buffer_stub.cc b/content/common/gpu/gpu_command_buffer_stub.cc
index b5392270f199015d5d2d6ce148fbd7162eb69d01..e9d30a78c3494406b06e1e47efddaddbe781adc0 100644
--- a/content/common/gpu/gpu_command_buffer_stub.cc
+++ b/content/common/gpu/gpu_command_buffer_stub.cc
@@ -395,14 +395,25 @@ void GpuCommandBufferStub::AcceleratedSurfaceBuffersSwapped(
 
   scheduler_->set_acknowledged_swap_buffers_count(swap_buffers_count);
 
-  for(uint64 i = 0; i < delta; i++)
+  for(uint64 i = 0; i < delta; i++) {
     OnSwapBuffers();
 
-  // Wake up the GpuScheduler to start doing work again.
-  scheduler_->SetScheduled(true);
+    // Wake up the GpuScheduler to start doing work again.
+    scheduler_->SetScheduled(true);

[jbates, 2011/06/07 16:47:52]

This was a bug that would allow the scheduled_count to get out of sync.

+  }
 }
 #endif  // defined(OS_MACOSX)
 
+void GpuCommandBufferStub::CommandBufferWasDestroyed() {
+  TRACE_EVENT0("gpu", "GpuCommandBufferStub::CommandBufferWasDestroyed");
+  while (!scheduler_->IsScheduled())
+    scheduler_->SetScheduled(true);
+  // Handle all deferred messages now, because the stub route is about to be
+  // removed by the GpuChannel. The PostTask handling may not work if the route
+  // is already removed.
+  HandleDeferredMessages();
+}
+
 void GpuCommandBufferStub::ResizeCallback(gfx::Size size) {
   if (handle_ == gfx::kNullPluginWindow) {
     scheduler_->decoder()->ResizeOffscreenFrameBuffer(size);