Bug 869151. Implement GetParent for nsCocoaWindow so that nsBaseWidget::Destroy can find the parent and remove from the child list when destroying. r=smichaud

widget/cocoa/nsCocoaWindow.h

@@ -216,6 +216,8 @@ public:
 
     NS_IMETHOD              Destroy();
 
+    virtual nsIWidget*      GetParent(void);
+
     NS_IMETHOD              Show(bool aState);
     virtual nsIWidget*      GetSheetWindowParent(void);
     NS_IMETHOD              Enable(bool aState);

widget/cocoa/nsCocoaWindow.mm

@@ -534,6 +534,11 @@ NS_IMETHODIMP nsCocoaWindow::Destroy()
   return NS_OK;
 }
 
+nsIWidget* nsCocoaWindow::GetParent()
+{
+  return mParent;
+}
+
 nsIWidget* nsCocoaWindow::GetSheetWindowParent(void)
 {
   if (mWindowType != eWindowType_sheet)