diff --git a/layout/style/nsStyleStruct.cpp b/layout/style/nsStyleStruct.cpp
index ac2a581b1b0..8a88cf57387 100644
--- a/layout/style/nsStyleStruct.cpp
+++ b/layout/style/nsStyleStruct.cpp
@@ -2249,30 +2249,26 @@ nsChangeHint nsStyleDisplay::CalcDifference(const nsStyleDisplay& aOther) const
                                          nsChangeHint_UpdateTransformLayer));
     }
 
+    const nsChangeHint kUpdateOverflowAndRepaintHint =
+      NS_CombineHint(nsChangeHint_UpdateOverflow, nsChangeHint_RepaintFrame);
     for (PRUint8 index = 0; index < 3; ++index)
       if (mTransformOrigin[index] != aOther.mTransformOrigin[index]) {
-        NS_UpdateHint(hint, NS_CombineHint(nsChangeHint_NeedReflow,
-                                           nsChangeHint_RepaintFrame));
+        NS_UpdateHint(hint, kUpdateOverflowAndRepaintHint);
         break;
       }
     
     for (PRUint8 index = 0; index < 2; ++index)
       if (mPerspectiveOrigin[index] != aOther.mPerspectiveOrigin[index]) {
-        NS_UpdateHint(hint, NS_CombineHint(nsChangeHint_NeedReflow,
-                                           nsChangeHint_RepaintFrame));
+        NS_UpdateHint(hint, kUpdateOverflowAndRepaintHint);
         break;
       }
 
-    if (mChildPerspective != aOther.mChildPerspective)
-      NS_UpdateHint(hint, NS_CombineHint(nsChangeHint_NeedReflow,
-                                         nsChangeHint_RepaintFrame));
+    if (mChildPerspective != aOther.mChildPerspective ||
+        mTransformStyle != aOther.mTransformStyle)
+      NS_UpdateHint(hint, kUpdateOverflowAndRepaintHint);
 
     if (mBackfaceVisibility != aOther.mBackfaceVisibility)
       NS_UpdateHint(hint, nsChangeHint_RepaintFrame);
-
-    if (mTransformStyle != aOther.mTransformStyle)
-      NS_UpdateHint(hint, NS_CombineHint(nsChangeHint_NeedReflow,
-                                         nsChangeHint_RepaintFrame));
   }
 
   // Note:  Our current behavior for handling changes to the