Bug 1456534 - Make sure we do a full display list rebuild on the next frame after creating a displayport during painting. r=mstange

MozReview-Commit-ID: 9SZMjf43G7S

--HG--
extra : rebase_source : 8d22bbb4aedf5e91ef2c20e4297cfde5292bf6e0

layout/generic/nsGfxScrollFrame.cpp

@@ -3673,6 +3673,7 @@ ScrollFrameHelper::BuildDisplayList(nsDisplayListBuilder*   aBuilder,
                     /* aSetBase = */ false, nullptr);
         if (mWillBuildScrollableLayer) {
           asrSetter.InsertScrollFrame(sf);
+          aBuilder->SetDisablePartialUpdates(true);
         }
       }
     }