diff --git a/mozilla/view/src/nsViewManager.h b/mozilla/view/src/nsViewManager.h
index 7352f2cfda5..573851bb688 100644
--- a/mozilla/view/src/nsViewManager.h
+++ b/mozilla/view/src/nsViewManager.h
@@ -25,6 +25,7 @@
 #include "nsIWidget.h"
 #include "nsITimer.h"
 #include "prtime.h"
+#include "prinrval.h"
 #include "nsVoidArray.h"
 #include "nsIScrollableView.h"
 #include "nsIRegion.h"