fix build bustage - use correct return type

widget/src/windows/nsAppShell.cpp

@@ -63,7 +63,7 @@ NS_METHOD nsAppShell::SetDispatchListener(nsDispatchListener* aDispatchListener)
 //
 //-------------------------------------------------------------------------
 
-nsresult nsAppShell::Run()
+NS_METHOD nsAppShell::Run()
 {
   NS_ADDREF_THIS();
     // Process messages

widget/src/windows/nsAppShell.h

@@ -38,7 +38,7 @@ class nsAppShell : public nsIAppShell
     // nsIAppShellInterface
   
     NS_IMETHOD            Create(int* argc, char ** argv);
-    virtual nsresult      Run(); 
+    NS_IMETHOD            Run(); 
     NS_IMETHOD            Spinup() { return NS_OK; }
     NS_IMETHOD            Spindown() { return NS_OK; }
     NS_IMETHOD            PushThreadEventQueue();