Virtual context MakeCurrent tweaks.

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 1e89262cf69d59725c83f582b379bdcc09af2c94..d6e245dc6cb761ff8ebe326c7ac81b4024b51627 100644
--- a/content/common/gpu/gpu_command_buffer_stub.cc
+++ b/content/common/gpu/gpu_command_buffer_stub.cc
@@ -360,23 +360,16 @@ void GpuCommandBufferStub::Destroy() {
                     destruction_observers_,
                     OnWillDestroyStub());
 
-  scoped_refptr<gfx::GLContext> context;
   if (decoder_) {
-    context = decoder_->GetGLContext();
+    // The surface destructor should be called with a current context.
+    // Therefore release the stub's reference before destroying the decoder,
+    // because the latter will release the context.
+    surface_ = NULL;

[epenner, 2013/05/28 22:57:21]

Are you sure this is the last valid reference to the surface? Could decoder_
have one until it is destroyed? It would be nice if we could DCHECK that this is
the last suface reference if we need that to be the case.

[no sievers, 2013/05/28 23:15:32]

Ah good point, I forgot to release the decoder's ref - see updated patch.

Otherwise, I think it's fine if multiple decoders share the surface, because the
last one going away would still make it current. In fact, that shouldn't have
behaved better before my patch. I added the error log now to catch bad usage
cases.

     decoder_->Destroy(have_context);
     decoder_.reset();
   }
 
   command_buffer_.reset();
-
-  // Make sure that context_ is current while we destroy surface_, because
-  // surface_ may have GL resources that it needs to destroy, and will need
-  // context_ to be current in order to not leak these resources.
-  if (context)
-    context->MakeCurrent(surface_.get());
-  surface_ = NULL;
-  if (context)
-    context->ReleaseCurrent(NULL);
 }
 
 void GpuCommandBufferStub::OnInitializeFailed(IPC::Message* reply_message) {