Merge 182954 "Don't bubble scrolls across boundary when scrollin..."

Source/core/frame/FrameView.cpp

Index: Source/core/frame/FrameView.cpp
===================================================================
--- Source/core/frame/FrameView.cpp	(revision 183206)
+++ Source/core/frame/FrameView.cpp	(working copy)
@@ -1815,10 +1815,18 @@
     if (anchorNode != m_frame->document())
         rect = anchorNode->boundingBox();
 
+    RefPtrWillBeRawPtr<LocalFrame> boundaryFrame = m_frame->document()->findUnsafeParentScrollPropagationBoundary();
+
+    if (boundaryFrame)
+        boundaryFrame->view()->setSafeToPropagateScrollToParent(false);
+
     // Scroll nested layers and frames to reveal the anchor.
     // Align to the top and to the closest side (this matches other browsers).
     anchorNode->renderer()->scrollRectToVisible(rect, ScrollAlignment::alignToEdgeIfNeeded, ScrollAlignment::alignTopAlways);
 
+    if (boundaryFrame)
+        boundaryFrame->view()->setSafeToPropagateScrollToParent(true);
+
     if (AXObjectCache* cache = m_frame->document()->existingAXObjectCache())
         cache->handleScrolledToAnchor(anchorNode.get());