Replace MessageLoop::DeleteSoon implementation with one that uses base::Bind.

base/message_loop.h

Index: base/message_loop.h
diff --git a/base/message_loop.h b/base/message_loop.h
index 28ccd4eefa825460b9c3e20b50dc52d0e7c9d49b..80c46dcf79214e50eb6b18b1cc05dced85771326 100644
--- a/base/message_loop.h
+++ b/base/message_loop.h
@@ -44,6 +44,14 @@
 
 namespace base {
 class Histogram;
+
+template <class T>

[awong, 2011/12/28 23:24:19]

This needs a comment explaining why we need this.

Basically, we need a template helper to "erase" T from the signature, while
still remembering it for use with deleting a pointer.  Embedding this in a class
makes it easier for users of DeleteSoon, etc., to declare this as a friend. And
lastly, no one but MessageLoop should call DoDelete.

BTW, is it worth making DoDelete() private and friending MessageLoop?

[dcheng, 2011/12/28 23:34:20]

Done. As discussed, made DoDelete private as well since all locations that
directly use DeleteTask will be converted to use DeleteSoon.

+class DeleteHelper {
+ public:
+  static void DoDelete(const void* object) {
+    delete reinterpret_cast<const T*>(object);
+  }
+};
 }
 
 // A MessageLoop is used to process events for a particular thread.  There is
@@ -208,7 +216,7 @@ class BASE_EXPORT MessageLoop : public base::MessagePump::Delegate {
   // from RefCountedThreadSafe<T>!
   template <class T>
   void DeleteSoon(const tracked_objects::Location& from_here, const T* object) {
-    PostNonNestableTask(from_here, new DeleteTask<T>(object));
+    DeleteSoonInternal(from_here, &base::DeleteHelper<T>::DoDelete, object);
   }
 
   // A variant on PostTask that releases the given reference counted object
@@ -532,6 +540,10 @@ class BASE_EXPORT MessageLoop : public base::MessagePump::Delegate {
   scoped_refptr<base::MessageLoopProxy> message_loop_proxy_;
 
  private:
+  void DeleteSoonInternal(const tracked_objects::Location& from_here,
+                          void(*deleter)(const void*),
+                          const void* object);
+
   DISALLOW_COPY_AND_ASSIGN(MessageLoop);
 };