GLInProcessContext: support async flushes and dedicated GPU thread

webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "webkit/common/gpu/webgraphicscontext3d_in_process_command_buffer_impl.h"
 
 #include <GLES2/gl2.h>
 #ifndef GL_GLEXT_PROTOTYPES
 #define GL_GLEXT_PROTOTYPES 1
 #endif
@@ skipping 1145 matching lines @@
   shallowFlushCHROMIUM();
   return 0;
 }
 
 void WebGraphicsContext3DInProcessCommandBufferImpl::signalSyncPoint(
     unsigned sync_point,
     WebGraphicsSyncPointCallback* callback) {
   // Take ownership of the callback.
   context_->SignalSyncPoint(
       sync_point, base::Bind(&OnSignalSyncPoint, base::Owned(callback)));
-  // Make sure we have something to flush, or shallowFlushCHROMIUM()
-  // doesn't do anything.
-  gl_->helper()->Noop(1);
-  // This fill force PumpCommands() to run which is what triggers the signal.
-  shallowFlushCHROMIUM();
 }
 
 void WebGraphicsContext3DInProcessCommandBufferImpl::signalQuery(
     unsigned query,
     WebGraphicsSyncPointCallback* callback) {
   // Take ownership of the callback.
   context_->SignalQuery(query,
                         base::Bind(&OnSignalSyncPoint, base::Owned(callback)));
 }
 
@@ skipping 10 matching lines @@
 
 DELEGATE_TO_GL_9(asyncTexSubImage2DCHROMIUM, AsyncTexSubImage2DCHROMIUM,
     WGC3Denum, WGC3Dint, WGC3Dint, WGC3Dint, WGC3Dsizei, WGC3Dsizei,
     WGC3Denum, WGC3Denum, const void*)
 
 DELEGATE_TO_GL_1(waitAsyncTexImage2DCHROMIUM, WaitAsyncTexImage2DCHROMIUM,
     WGC3Denum)
 
 }  // namespace gpu
 }  // namespace webkit