Fix the build when use_glib is set to 0.

base/message_loop/message_loop.h

 // Copyright 2013 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 BASE_MESSAGE_LOOP_MESSAGE_LOOP_H_
 #define BASE_MESSAGE_LOOP_MESSAGE_LOOP_H_
 
 #include <queue>
 #include <string>
 
@@ skipping 536 matching lines @@
 #endif
 
 #if defined(OS_WIN)
   typedef MessagePumpObserver Observer;
 
   // Please see message_pump_win for definitions of these methods.
   void AddObserver(Observer* observer);
   void RemoveObserver(Observer* observer);
 #endif
 
-#if defined(USE_OZONE) || (defined(OS_CHROMEOS) && !defined(USE_GLIB))
+#if defined(USE_OZONE) || (defined(OS_CHROMEOS) && !defined(USE_GLIB)) || \
+    (defined(OS_LINUX) && !defined(USE_GLIB))

[zhaoze.zhou, 2014/07/15 21:33:10]

this function is needed x11_event_source_libevent.cc even if we do not use the
glib

[sadrul, 2014/07/15 21:34:41]

Do you mean:

  USE_OZONE || (USE_X11 && !USE_GLIB)

?

   // Please see MessagePumpLibevent for definition.
   bool WatchFileDescriptor(
       int fd,
       bool persistent,
       MessagePumpLibevent::Mode mode,
       MessagePumpLibevent::FileDescriptorWatcher* controller,
       MessagePumpLibevent::Watcher* delegate);
 #endif
 };
 
@@ skipping 80 matching lines @@
 
 // Do not add any member variables to MessageLoopForIO!  This is important b/c
 // MessageLoopForIO is often allocated via MessageLoop(TYPE_IO).  Any extra
 // data that you need should be stored on the MessageLoop's pump_ instance.
 COMPILE_ASSERT(sizeof(MessageLoop) == sizeof(MessageLoopForIO),
                MessageLoopForIO_should_not_have_extra_member_variables);
 
 }  // namespace base
 
 #endif  // BASE_MESSAGE_LOOP_MESSAGE_LOOP_H_