Bug 1382534 - Use GetBounds() in nsDisplayMask::ComputeVisibility(). r=mstange

The code previously used GetClippedBoundsWithRespectToASR() (changed
in bug 1298218), but this violated the requirements of nsDisplayList::
ComputeVisibilityForSublist().

MozReview-Commit-ID: F9UVMvVKLAp

--HG--
extra : rebase_source : ec188650070d4e8de1b19395c3ed6f31e7d0e04f

layout/painting/nsDisplayList.cpp

@@ -9299,8 +9299,7 @@ bool nsDisplayMask::ComputeVisibility(nsDisplayListBuilder* aBuilder,
   // Our children may be made translucent or arbitrarily deformed so we should
   // not allow them to subtract area from aVisibleRegion.
   nsRegion childrenVisible(mVisibleRect);
-  nsRect r = mVisibleRect.Intersect(
-    mList.GetClippedBoundsWithRespectToASR(aBuilder, mActiveScrolledRoot));
+  nsRect r = mVisibleRect.Intersect(mList.GetBounds(aBuilder));
   mList.ComputeVisibilityForSublist(aBuilder, &childrenVisible, r);
   return true;
 }