Update {virtual,override} to follow C++11 style in ppapi.

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 34 matching lines @@
     // on the other side of the channel. This is part of the delegate interface
     // because both sides of the channel may not have sufficient permission to
     // duplicate handles directly. The implementation must provide the same
     // guarantees as ProxyChannel::ShareHandleWithRemote below.
     virtual IPC::PlatformFileForTransit ShareHandleWithRemote(
         base::PlatformFile handle,
         base::ProcessId remote_pid,
         bool should_close_source) = 0;
   };
 
-  virtual ~ProxyChannel();
+  ~ProxyChannel() override;
 
   // Alternative to InitWithChannel() for unit tests that want to send all
   // messages sent via this channel to the given test sink. The test sink
   // must outlive this class. In this case, the peer PID will be the current
   // process ID.
   void InitWithTestSink(IPC::TestSink* test_sink);
 
   // Shares a file handle (HANDLE / file descriptor) with the remote side. It
   // returns a handle that should be sent in exactly one IPC message. Upon
   // receipt, the remote side then owns that handle. Note: if sending the
   // 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;
+  bool Send(IPC::Message* msg) override;
 
   // IPC::Listener implementation.
-  virtual void OnChannelError() override;
+  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();
 #endif
 
@@ skipping 30 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_