Hold the Pepper proxy lock for all Pepper GL calls.

ppapi/proxy/plugin_dispatcher.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_PLUGIN_DISPATCHER_H_
 #define PPAPI_PROXY_PLUGIN_DISPATCHER_H_
 
 #include <set>
 #include <string>
 
@@ skipping 122 matching lines @@
 
   // You must call this function before anything else. Returns true on success.
   // The delegate pointer must outlive this class, ownership is not
   // transferred.
   bool InitPluginWithChannel(PluginDelegate* delegate,
                              base::ProcessId peer_pid,
                              const IPC::ChannelHandle& channel_handle,
                              bool is_client);
 
   // Dispatcher overrides.
-  virtual bool IsPlugin() const;
-  virtual bool Send(IPC::Message* msg);
+  bool IsPlugin() const override;
+  bool Send(IPC::Message* msg) override;
+  // Unlike |Send()|, this function continues to hold the Pepper proxy lock
+  // unconditionally.
+  bool SendAndStayLocked(IPC::Message* msg) override;
 
   // IPC::Listener implementation.
-  virtual bool OnMessageReceived(const IPC::Message& msg);
-  virtual void OnChannelError();
+  bool OnMessageReceived(const IPC::Message& msg) override;
+  void OnChannelError() override;
 
   // Keeps track of which dispatcher to use for each instance, active instances
   // and tracks associated data like the current size.
   void DidCreateInstance(PP_Instance instance);
   void DidDestroyInstance(PP_Instance instance);
 
   // Gets the data for an existing instance, or NULL if the instance id doesn't
   // correspond to a known instance.
   InstanceData* GetInstanceData(PP_Instance instance);
 
@@ skipping 47 matching lines @@
   // A filter for sending messages from threads other than the main thread.
   scoped_refptr<IPC::SyncMessageFilter> sync_filter_;
 
   DISALLOW_COPY_AND_ASSIGN(PluginDispatcher);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_PLUGIN_DISPATCHER_H_