ChannelMojo: Handle when ChannelMojo outlives ChannelMojoHost

ipc/mojo/ipc_channel_mojo.cc

 // 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.
 
 #include "ipc/mojo/ipc_channel_mojo.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/lazy_instance.h"
 #include "ipc/ipc_listener.h"
@@ skipping 65 matching lines @@
     const ChannelHandle& channel_handle) {
   return make_scoped_ptr(
              new MojoChannelFactory(NULL, channel_handle, Channel::MODE_CLIENT))
       .PassAs<ChannelFactory>();
 }
 
 ChannelMojo::ChannelMojo(ChannelMojoHost* host,
                          const ChannelHandle& handle,
                          Mode mode,
                          Listener* listener)
-    : host_(host),
+    : host_(host ? host->ToWeakPtr() : base::WeakPtr<ChannelMojoHost>()),

[viettrungluu, 2014/09/25 19:38:34]

Maybe it's better to just do in the body:

if (host) {
  host_ = host->ToWeakPtr();
  host_->OnChannelCreated(...);
}

[Hajime Morrita, 2014/09/25 22:00:03]

Done.

       mode_(mode),
       listener_(listener),
       peer_pid_(base::kNullProcessId),
       weak_factory_(this) {
   // Create MojoBootstrap after all members are set as it touches
   // ChannelMojo from a different thread.
   bootstrap_ = MojoBootstrap::Create(handle, mode, this);
   if (host_)
-    host_->OnChannelCreated(this);
+    host_->OnChannelCreated(weak_factory_.GetWeakPtr());
 }
 
 ChannelMojo::~ChannelMojo() {
   Close();
-
-  if (host_)
-    host_->OnChannelDestroyed();
 }
 
 void ChannelMojo::InitControlReader(
     mojo::embedder::ScopedPlatformHandle handle) {
   DCHECK(base::MessageLoopForIO::IsCurrent());
   mojo::embedder::ChannelInfo* channel_info;
   mojo::ScopedMessagePipeHandle control_pipe =
       mojo::embedder::CreateChannelOnIOThread(handle.Pass(), &channel_info);
   channel_info_.reset(channel_info);
 
@@ skipping 153 matching lines @@
       handles->push_back(wrapped_handle);
     }
   }
 
   return MOJO_RESULT_OK;
 }
 
 #endif  // defined(OS_POSIX) && !defined(OS_NACL)
 
 }  // namespace IPC