Delete watcher on IO thread in MessagePumpLibeventTest.QuitWatcher.

base/message_loop/message_pump_libevent_unittest.cc

 // 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.
 
 #include "base/message_loop/message_pump_libevent.h"
 
 #include <unistd.h>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 228 matching lines @@
 TEST_F(MessagePumpLibeventTest, QuitWatcher) {
   // Delete the old MessageLoop so that we can manage our own one here.
   ui_loop_.reset();
 
   MessagePumpLibevent* pump = new MessagePumpLibevent;  // owned by |loop|.
   MessageLoop loop(make_scoped_ptr(pump));
   RunLoop run_loop;
   MessagePumpLibevent::FileDescriptorWatcher controller;
   QuitWatcher delegate(&controller, &run_loop);
   WaitableEvent event(false /* manual_reset */, false /* initially_signaled */);
-  WaitableEventWatcher watcher;
+  scoped_ptr<WaitableEventWatcher> watcher(new WaitableEventWatcher);
 
   // Tell the pump to watch the pipe.
   pump->WatchFileDescriptor(pipefds_[0], false, MessagePumpLibevent::WATCH_READ,
                             &controller, &delegate);
 
   // Make the IO thread wait for |event| before writing to pipefds[1].
   const char buf = 0;
   const WaitableEventWatcher::EventCallback write_fd_task =
       Bind(&WriteFDWrapper, pipefds_[1], &buf, 1);
   io_loop()->PostTask(FROM_HERE,
                       Bind(IgnoreResult(&WaitableEventWatcher::StartWatching),
-                           Unretained(&watcher), &event, write_fd_task));
+                           Unretained(watcher.get()), &event, write_fd_task));
 
   // Queue |event| to signal on |loop|.
   loop.PostTask(FROM_HERE, Bind(&WaitableEvent::Signal, Unretained(&event)));
 
   // Now run the MessageLoop.
   run_loop.Run();
+
+  // StartWatching can move |watcher| to IO thread. Release on IO thread.
+  io_loop()->PostTask(FROM_HERE, Bind(&WaitableEventWatcher::StopWatching,
+                                      Unretained(watcher.get())));

[Chirantan Ekbote, 2015/06/20 00:09:37]

Why not just use base::Passed here?

[derekjchow1, 2015/06/20 00:34:07]

I don't think we can Pass a scoped_ptr as the "this" argument to a class method.
That being said, we can probably use base::Owned.

https://code.google.com/p/chromium/codesearch#chromium/src/base/callback.h&q=...

+  io_loop()->DeleteSoon(FROM_HERE, watcher.release());
 }
 
 }  // namespace
 
 }  // namespace base