Bug 1189964 - Fix bustage. r=bustage CLOSED TREE

--HG--
extra : amend_source : c36fd335a82e19124f639c572b2348e612d104a1

dom/ipc/TabParent.cpp

@@ -3240,7 +3240,7 @@ TabParent::RecvInvokeDragSession(nsTArray<IPCDataTransfer>&& aTransfers,
   nsIPresShell* shell = mFrameElement->OwnerDoc()->GetShell();
   if (!shell) {
     if (Manager()->IsContentParent()) {
-      Manager()->AsContentParent()->SendEndDragSession(true, true);
+      unused << Manager()->AsContentParent()->SendEndDragSession(true, true);
     }
     return true;
   }