Hold the Pepper proxy lock for all Pepper GL calls.

ppapi/proxy/proxy_channel.h

 // 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.
 
 #ifndef PPAPI_PROXY_PROXY_CHANNEL_H_
 #define PPAPI_PROXY_PROXY_CHANNEL_H_
 
 #include "base/files/scoped_file.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/process/process.h"
@@ skipping 55 matching lines @@
   // message fails, the returned handle is properly closed by the IPC system. If
   // should_close_source is set to true, the original handle is closed by this
   // operation and should not be used again.
   IPC::PlatformFileForTransit ShareHandleWithRemote(
       base::PlatformFile handle,
       bool should_close_source);
 
   // IPC::Sender implementation.
   virtual bool Send(IPC::Message* msg) override;
 
+  virtual bool SendAndStayLocked(IPC::Message* msg);
+
   // IPC::Listener implementation.
   virtual void OnChannelError() override;
 
   // Will be NULL in some unit tests and if the remote side has crashed.
   IPC::SyncChannel* channel() const {
     return channel_.get();
   }
 
 #if defined(OS_POSIX) && !defined(OS_NACL)
   base::ScopedFD TakeRendererFD();
@@ skipping 32 matching lines @@
   // remote side has crashed.
   scoped_ptr<IPC::SyncChannel> channel_;
 
   DISALLOW_COPY_AND_ASSIGN(ProxyChannel);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_PROXY_CHANNEL_H_