Rewrite most of the scopers in //base/mac to use ScopedTypeRef or ScopedGeneric.

base/message_loop/message_pump_io_ios_unittest.cc

Index: base/message_loop/message_pump_io_ios_unittest.cc
diff --git a/base/message_loop/message_pump_io_ios_unittest.cc b/base/message_loop/message_pump_io_ios_unittest.cc
index ed3946875da30c7c416257e67a8f3e437b267752..e51de70c0e0e88322fe5ef65e0a8d7a81ccd7436 100644
--- a/base/message_loop/message_pump_io_ios_unittest.cc
+++ b/base/message_loop/message_pump_io_ios_unittest.cc
@@ -44,7 +44,7 @@ class MessagePumpIOSForIOTest : public testing::Test {
   }
 
   void HandleFdIOEvent(MessageLoopForIO::FileDescriptorWatcher* watcher) {
-    MessagePumpIOSForIO::HandleFdIOEvent(watcher->fdref_,
+    MessagePumpIOSForIO::HandleFdIOEvent(watcher->fdref_.get(),
         kCFFileDescriptorReadCallBack | kCFFileDescriptorWriteCallBack,
         watcher);
   }