Implement MessageLoopForUI using GLib. This gets some exercise from...

base/message_loop.cc

 // Copyright (c) 2006-2008 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.h"
 
 #include <algorithm>
 
 #include "base/compiler_specific.h"
 #include "base/lazy_instance.h"
 #include "base/logging.h"
 #include "base/message_pump_default.h"
 #include "base/string_util.h"
 #include "base/thread_local.h"
 
 #if defined(OS_MACOSX)
 #include "base/message_pump_mac.h"
 #endif
 #if defined(OS_POSIX)
 #include "base/message_pump_libevent.h"
 #endif
+#if defined(OS_LINUX)
+#include "base/message_pump_glib.h"
+#endif
 
 // A lazily created thread local storage for quick access to a thread's message
 // loop, if one exists.  This should be safe and free of static constructors.
 static base::LazyInstance<base::ThreadLocalPointer<MessageLoop> > lazy_tls_ptr(
     base::LINKER_INITIALIZED);
 
 //------------------------------------------------------------------------------
 
 // Logical events for Histogram profiling. Run with -message-loop-histogrammer
 // to get an accounting of messages and actions taken on each thread.
@@ skipping 50 matching lines @@
   // TODO(rvargas): Get rid of the OS guards.
   if (type_ == TYPE_DEFAULT) {
     pump_ = new base::MessagePumpDefault();
   } else if (type_ == TYPE_IO) {
     pump_ = new base::MessagePumpForIO();
   } else {
     DCHECK(type_ == TYPE_UI);
     pump_ = new base::MessagePumpForUI();
   }
 #elif defined(OS_POSIX)
+  if (type_ == TYPE_UI) {
 #if defined(OS_MACOSX)
-  if (type_ == TYPE_UI) {
     pump_ = base::MessagePumpMac::Create();
-  } else
-#endif  // OS_MACOSX
-  if (type_ == TYPE_IO) {
+#elif defined(OS_LINUX)
+    pump_ = new base::MessagePumpForUI();
+#endif  // OS_LINUX
+  } else if (type_ == TYPE_IO) {
     pump_ = new base::MessagePumpLibevent();
   } else {
     pump_ = new base::MessagePumpDefault();
   }
-#else  // OS_POSIX
-  pump_ = new base::MessagePumpDefault();
 #endif  // OS_POSIX
 }
 
 MessageLoop::~MessageLoop() {
   DCHECK(this == current());
 
   // Let interested parties have one last shot at accessing this.
   FOR_EACH_OBSERVER(DestructionObserver, destruction_observers_,
                     WillDestroyCurrentMessageLoop());
 
@@ skipping 472 matching lines @@
 
 void MessageLoopForIO::WatchSocket(int socket, short interest_mask, 
                                    struct event* e, Watcher* watcher) {
   pump_libevent()->WatchSocket(socket, interest_mask, e, watcher);
 }
 
 void MessageLoopForIO::UnwatchSocket(struct event* e) {
   pump_libevent()->UnwatchSocket(e);
 }
 #endif