345425 onDragExit in tabbrowser.xml is called with aDragSession.sourceNode null when a tab is dropped on itself. Eliminate extra call to EndDragSession. r=josh sr=pink

widget/src/mac/nsDragHelperService.cpp

@@ -239,10 +239,6 @@ nsDragHelperService::Drop(DragReference inDragRef, nsIEventSink *inSink,
         result = dragNotAcceptedErr;
   } // if a valid drag session
 
-  // we don't need the drag session anymore, the user has released the
-  // mouse and the event has already gone to gecko.
-  mDragService->EndDragSession();
-
   // if there was any kind of error, the drag wasn't accepted
   *outAccepted = (result == noErr);
 

widget/src/mac/nsDragService.cpp

@@ -236,7 +236,7 @@ nsDragService::ComputeGlobalRectFromFrame ( nsIDOMNode* aDOMNode, Rect & outScre
 
 
 //
-// StartDragSession
+// InvokeDragSession
 //
 // Do all the work to kick it off.
 //
@@ -326,7 +326,7 @@ nsDragService::InvokeDragSession (nsIDOMNode *aDOMNode, nsISupportsArray * aTran
 
   return NS_OK; 
 
-} // StartDragSession
+} // InvokeDragSession
 
 
 //
@@ -1163,26 +1163,6 @@ nsDragService::ExtractDataFromOS ( DragReference inDragRef, ItemReference inItem
 } // ExtractDataFromOS
 
 
-//
-// StartDragSession
-// EndDragSession
-//
-// Override the defaults to disable/enable the watch cursor while we're dragging
-//
-
-nsresult
-nsDragService::StartDragSession ( )
-{
-  return nsBaseDragService::StartDragSession();
-}
-
-nsresult
-nsDragService::EndDragSession ( )
-{
-  return nsBaseDragService::EndDragSession();
-}
-
-
 //
 // SetDragAction
 //

widget/src/mac/nsDragService.h

@@ -79,9 +79,6 @@ public:
 
 private:
 
-  NS_IMETHOD StartDragSession ( ) ;
-  NS_IMETHOD EndDragSession ( ) ;
-  
   char* LookupMimeMappingsForItem ( DragReference inDragRef, ItemReference itemRef ) ;
 
   void RegisterDragItemsAndFlavors ( nsISupportsArray * inArray, RgnHandle inDragRgn ) ;

widget/src/mac/nsMacEventHandler.cpp

@@ -574,7 +574,7 @@ PRBool nsMacEventHandler::DragEvent(unsigned int aMessage,
         // done when aMessage == NS_DRAGDROP_EXIT, because that indicates
         // that the drag is leaving the window.
 
-        nsMouseEvent enterEvent(PR_TRUE, NS_DRAGDROP_EXIT, widgetHit,
+        nsMouseEvent enterEvent(PR_TRUE, NS_DRAGDROP_ENTER, widgetHit,
                                 nsMouseEvent::eReal);
         InitializeMouseEvent(enterEvent, widgetHitPoint, aKeyModifiers, 1);
         widgetHit->DispatchMouseEvent(enterEvent);