Give a CFRunLoop to the IO message loop type on Mac OS X.

base/message_loop.h

Index: base/message_loop.h
===================================================================
--- base/message_loop.h	(revision 90809)
+++ base/message_loop.h	(working copy)
@@ -24,9 +24,10 @@
 // We need this to declare base::MessagePumpWin::Dispatcher, which we should
 // really just eliminate.
 #include "base/message_pump_win.h"
+#elif defined(OS_MACOSX)
+#include "base/message_pump_mac.h"
 #elif defined(OS_POSIX)
 #include "base/message_pump_libevent.h"
-#if !defined(OS_MACOSX)
 #if defined(TOUCH_UI)
 #include "base/message_pump_x.h"
 #else
@@ -34,7 +35,6 @@
 #endif
 typedef struct _XDisplay Display;
 #endif
-#endif
 
 namespace base {
 class Histogram;
@@ -431,6 +431,10 @@
   base::MessagePumpWin* pump_win() {
     return static_cast<base::MessagePumpWin*>(pump_.get());
   }
+#elif defined(OS_MACOSX)
+  base::MessagePumpCFRunLoopBase* pump_mac() {
+    return static_cast<base::MessagePumpCFRunLoopBase*>(pump_.get());
+  }
 #elif defined(OS_POSIX)
   base::MessagePumpLibevent* pump_libevent() {
     return static_cast<base::MessagePumpLibevent*>(pump_.get());
@@ -630,6 +634,17 @@
   typedef base::MessagePumpForIO::IOHandler IOHandler;
   typedef base::MessagePumpForIO::IOContext IOContext;
   typedef base::MessagePumpForIO::IOObserver IOObserver;
+#elif defined(OS_MACOSX)
+  typedef base::MessagePumpCFRunLoopBase::Watcher Watcher;
+  typedef base::MessagePumpCFRunLoopBase::FileDescriptorWatcher
+      FileDescriptorWatcher;
+  typedef base::MessagePumpCFRunLoopBase::IOObserver IOObserver;
+
+  enum Mode {
+    WATCH_READ = base::MessagePumpCFRunLoopBase::WATCH_READ,
+    WATCH_WRITE = base::MessagePumpCFRunLoopBase::WATCH_WRITE,
+    WATCH_READ_WRITE = base::MessagePumpCFRunLoopBase::WATCH_READ_WRITE
+  };
 #elif defined(OS_POSIX)
   typedef base::MessagePumpLibevent::Watcher Watcher;
   typedef base::MessagePumpLibevent::FileDescriptorWatcher
@@ -641,7 +656,6 @@
     WATCH_WRITE = base::MessagePumpLibevent::WATCH_WRITE,
     WATCH_READ_WRITE = base::MessagePumpLibevent::WATCH_READ_WRITE
   };
-
 #endif
 
   MessageLoopForIO() : MessageLoop(TYPE_IO) {
@@ -673,6 +687,18 @@
     return static_cast<base::MessagePumpForIO*>(pump_.get());
   }
 
+#elif defined(OS_MACOSX)
+  // Please see MessagePumpCFRunLoopBase for definition.
+  bool WatchFileDescriptor(int fd,
+                           bool persistent,
+                           Mode mode,
+                           FileDescriptorWatcher *controller,
+                           Watcher *delegate);
+
+ private:
+  base::MessagePumpCFRunLoopBase* pump_io() {
+    return static_cast<base::MessagePumpCFRunLoopBase*>(pump_.get());
+  }
 #elif defined(OS_POSIX)
   // Please see MessagePumpLibevent for definition.
   bool WatchFileDescriptor(int fd,