IPC: Delete thread-safe send support

ipc/ipc_sync_message_filter.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 IPC_IPC_SYNC_MESSAGE_FILTER_H_
 #define IPC_IPC_SYNC_MESSAGE_FILTER_H_
 
 #include <set>
 #include <vector>
 
@@ skipping 25 matching lines @@
   // MessageSender implementation.
   bool Send(Message* message) override;
 
   // MessageFilter implementation.
   void OnFilterAdded(Sender* sender) override;
   void OnChannelError() override;
   void OnChannelClosing() override;
   bool OnMessageReceived(const Message& message) override;
 
  protected:
-  SyncMessageFilter(base::WaitableEvent* shutdown_event,
-                    bool is_channel_send_thread_safe);
-
+  explicit SyncMessageFilter(base::WaitableEvent* shutdown_event);
   ~SyncMessageFilter() override;
 
  private:
   class IOMessageLoopObserver;
 
   friend class SyncChannel;
   friend class IOMessageLoopObserver;
 
-  void set_is_channel_send_thread_safe(bool is_channel_send_thread_safe) {
-    is_channel_send_thread_safe_ = is_channel_send_thread_safe;
-  }
-
   void SendOnIOThread(Message* message);
   // Signal all the pending sends as done, used in an error condition.
   void SignalAllEvents();
 
   void OnShutdownEventSignaled(base::WaitableEvent* event);
   void OnIOMessageLoopDestroyed();
 
   // The channel to which this filter was added.
   Sender* sender_;
 
-  // Indicates if |sender_|'s Send method is thread-safe.
-  bool is_channel_send_thread_safe_;
-
   // The process's main thread.
   scoped_refptr<base::SingleThreadTaskRunner> listener_task_runner_;
 
   // The message loop where the Channel lives.
   scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
 
   typedef std::set<PendingSyncMsg*> PendingSyncMessages;
   PendingSyncMessages pending_sync_messages_;
 
   // Messages waiting to be delivered after IO initialization.
@@ skipping 15 matching lines @@
   scoped_refptr<IOMessageLoopObserver> io_message_loop_observer_;
 
   base::WeakPtrFactory<SyncMessageFilter> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SyncMessageFilter);
 };
 
 }  // namespace IPC
 
 #endif  // IPC_IPC_SYNC_MESSAGE_FILTER_H_