WebGraphicsContext3DCommandBufferImpl::genMailboxCHROMIUIM is not a synchronous command.

content/common/gpu/client/webgraphicscontext3d_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 "content/common/gpu/client/webgraphicscontext3d_command_buffer_impl.h"
 
 #include "third_party/khronos/GLES2/gl2.h"
 #ifndef GL_GLEXT_PROTOTYPES
 #define GL_GLEXT_PROTOTYPES 1
 #endif
@@ skipping 1568 matching lines @@
                  WebGLId, WGC3Denum, WGC3Duint*)
 
 DELEGATE_TO_GL_5(copyTextureCHROMIUM, CopyTextureCHROMIUM,  WGC3Denum,
                  WebGLId, WebGLId, WGC3Dint, WGC3Denum);
 
 DELEGATE_TO_GL_3(bindUniformLocationCHROMIUM, BindUniformLocationCHROMIUM,
                  WebGLId, WGC3Dint, const WGC3Dchar*)
 
 DELEGATE_TO_GL(shallowFlushCHROMIUM,ShallowFlushCHROMIUM);
 
-DELEGATE_TO_GL_1(genMailboxCHROMIUM, GenMailboxCHROMIUM, WGC3Dbyte*)
+void WebGraphicsContext3DCommandBufferImpl::genMailboxCHROMIUM(
+    WGC3Dbyte* name) {
+  std::vector<std::string> names(1);
+  if (command_buffer_->GenerateMailboxNames(1, &names))
+    memcpy(name, names[0].c_str(), GL_MAILBOX_SIZE_CHROMIUM);
+  else
+    synthesizeGLError(GL_OUT_OF_MEMORY);
+}
+
 DELEGATE_TO_GL_2(produceTextureCHROMIUM, ProduceTextureCHROMIUM,
                  WGC3Denum, const WGC3Dbyte*)
 DELEGATE_TO_GL_2(consumeTextureCHROMIUM, ConsumeTextureCHROMIUM,
                  WGC3Denum, const WGC3Dbyte*)
 
 void WebGraphicsContext3DCommandBufferImpl::insertEventMarkerEXT(
     const WGC3Dchar* marker) {
   gl_->InsertEventMarkerEXT(0, marker);
 }
 
@@ skipping 59 matching lines @@
 
 void WebGraphicsContext3DCommandBufferImpl::OnErrorMessage(
     const std::string& message, int id) {
   if (error_message_callback_) {
     WebKit::WebString str = WebKit::WebString::fromUTF8(message.c_str());
     error_message_callback_->onErrorMessage(str, id);
   }
 }
 
 }  // namespace content