Improve MessageLoop's comments.

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 176 matching lines @@
   void PostNonNestableDelayedTask(const tracked_objects::Location& from_here,
                                   const Closure& task,
                                   TimeDelta delay);
 
   // A variant on PostTask that deletes the given object.  This is useful
   // if the object needs to live until the next run of the MessageLoop (for
   // example, deleting a RenderProcessHost from within an IPC callback is not
   // good).
   //
   // NOTE: This method may be called on any thread.  The object will be deleted
-  // on the thread that executes MessageLoop::Run().  If this is not the same
-  // as the thread that calls PostDelayedTask(FROM_HERE, ), then T MUST inherit
-  // from RefCountedThreadSafe<T>!
+  // on the thread that executes MessageLoop::Run().
   template <class T>
   void DeleteSoon(const tracked_objects::Location& from_here, const T* object) {
     base::subtle::DeleteHelperInternal<T, void>::DeleteViaSequencedTaskRunner(
         this, from_here, object);
   }
 
   // A variant on PostTask that releases the given reference counted object
   // (by calling its Release method).  This is useful if the object needs to
   // live until the next run of the MessageLoop, or if the object needs to be
   // released on a particular thread.
   //
   // A common pattern is to manually increment the object's reference count
   // (AddRef), clear the pointer, then issue a ReleaseSoon.  The reference count
   // is incremented manually to ensure clearing the pointer does not trigger a
   // delete and to account for the upcoming decrement (ReleaseSoon).  For
   // example:
   //
   // scoped_refptr<Foo> foo = ...
   // foo->AddRef();
   // Foo* raw_foo = foo.get();
   // foo = NULL;
   // message_loop->ReleaseSoon(raw_foo);
   //
   // NOTE: This method may be called on any thread.  The object will be
   // released (and thus possibly deleted) on the thread that executes
   // MessageLoop::Run().  If this is not the same as the thread that calls
-  // PostDelayedTask(FROM_HERE, ), then T MUST inherit from
+  // ReleaseSoon(FROM_HERE, ), then T MUST inherit from
   // RefCountedThreadSafe<T>!
   template <class T>
   void ReleaseSoon(const tracked_objects::Location& from_here,
                    const T* object) {
     base::subtle::ReleaseHelperInternal<T, void>::ReleaseViaSequencedTaskRunner(
         this, from_here, object);
   }
 
   // Deprecated: use RunLoop instead.
   // Run the message loop.
@@ skipping 413 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_