Bug 1182017. Call Send__delete__ immediately rather than through an event. r=nical

Kyle assures me it's safe to call Send__delete__ with references to 'this' on
the stack.

--HG--
extra : commitid : I7Wj1a8Hmb9
extra : rebase_source : 8cf8851a7f4400fb1120179423ec4cf710d75765

gfx/layers/ipc/ImageContainerParent.cpp

@@ -20,16 +20,9 @@ ImageContainerParent::~ImageContainerParent()
   }
 }
 
-static void SendDeleteAndIgnoreResult(ImageContainerParent* self)
-{
-  unused << PImageContainerParent::Send__delete__(self);
-}
-
 bool ImageContainerParent::RecvAsyncDelete()
 {
-  MessageLoop::current()->PostTask(
+  unused << PImageContainerParent::Send__delete__(this);
-    FROM_HERE, NewRunnableFunction(&SendDeleteAndIgnoreResult, this));
-
   return true;
 }