Fix crash in FrameView::updateLayersAndCompositingAfterScrollIfNeeded

third_party/WebKit/Source/core/frame/FrameView.cpp

Index: third_party/WebKit/Source/core/frame/FrameView.cpp
diff --git a/third_party/WebKit/Source/core/frame/FrameView.cpp b/third_party/WebKit/Source/core/frame/FrameView.cpp
index 5bf6441258d162eeb96671455bca7962985f2ab5..a363fe6cf6b423cbfde5f49ea129e77c3360414f 100644
--- a/third_party/WebKit/Source/core/frame/FrameView.cpp
+++ b/third_party/WebKit/Source/core/frame/FrameView.cpp
@@ -1974,6 +1974,13 @@ void FrameView::updateLayersAndCompositingAfterScrollIfNeeded() {
       continue;
 
     PaintLayer* layer = toLayoutBoxModelObject(layoutObject)->layer();
+
+    // This method can be called during layout at which point the ancestor
+    // overflow layer may not be set yet. We can safely skip such cases as we
+    // will revisit this method during compositing inputs update.
+    if (!layer->ancestorOverflowLayer())
+      continue;
+
     StickyConstraintsMap constraintsMap = layer->ancestorOverflowLayer()
                                               ->getScrollableArea()
                                               ->stickyConstraintsMap();