ChannelProxy: Send() from UI thread when ChannelMojo is used.

ipc/mojo/ipc_channel_mojo.h

 // Copyright 2014 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 IPC_IPC_CHANNEL_MOJO_H_
 #define IPC_IPC_CHANNEL_MOJO_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/memory/weak_ptr.h"
+#include "base/synchronization/lock.h"
 #include "ipc/ipc_channel.h"
 #include "ipc/ipc_channel_factory.h"
 #include "ipc/ipc_export.h"
 #include "ipc/mojo/ipc_message_pipe_reader.h"
 #include "ipc/mojo/ipc_mojo_bootstrap.h"
 #include "mojo/edk/embedder/channel_info_forward.h"
 #include "mojo/public/cpp/system/core.h"
 
 namespace IPC {
 
@@ skipping 56 matching lines @@
 
   ~ChannelMojo() override;
 
   // ChannelMojoHost tells the client handle using this API.
   void OnClientLaunched(base::ProcessHandle handle);
 
   // Channel implementation
   bool Connect() override;
   void Close() override;
   bool Send(Message* message) override;
+  bool IsSendThreadSafe() const override;
   base::ProcessId GetPeerPID() const override;
   base::ProcessId GetSelfPID() const override;
 
 #if defined(OS_POSIX) && !defined(OS_NACL)
   int GetClientFileDescriptor() const override;
   base::ScopedFD TakeClientFileDescriptor() override;
 
   // These access protected API of IPC::Message, which has ChannelMojo
   // as a friend class.
   static MojoResult WriteToFileDescriptorSet(
@@ skipping 29 matching lines @@
   struct ChannelInfoDeleter {
     void operator()(mojo::embedder::ChannelInfo* ptr) const;
   };
 
   // ChannelMojo needs to kill its MessagePipeReader in delayed manner
   // because the channel wants to kill these readers during the
   // notifications invoked by them.
   typedef internal::MessagePipeReader::DelayedDeleter ReaderDeleter;
 
   void InitDelegate(ChannelMojo::Delegate* delegate);
+  base::TaskRunner* GetIOTaskRunner();
 
   scoped_ptr<MojoBootstrap> bootstrap_;
-  base::WeakPtr<Delegate> delegate_;
   Mode mode_;
   Listener* listener_;
   base::ProcessId peer_pid_;
   scoped_ptr<mojo::embedder::ChannelInfo,
              ChannelInfoDeleter> channel_info_;
 
+  // Guards |message_reader_|, |pending_messages_| and |delegate_|.
+  //
+  // * The contents of |pending_messages_| can be modified from any threads.
+  // * |delegate_| and |message_reader_| is modified only from IO thread,
+  //   but they can be referred from other threads.
+  base::Lock lock_;
+  base::WeakPtr<Delegate> delegate_;
   scoped_ptr<internal::MessagePipeReader, ReaderDeleter> message_reader_;
   ScopedVector<Message> pending_messages_;
 
   base::WeakPtrFactory<ChannelMojo> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ChannelMojo);
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_CHANNEL_MOJO_H_