Disable scroll anchoring if the user engages in a drag motion

third_party/WebKit/Source/core/paint/PaintInvalidationCapableScrollableArea.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/paint/PaintInvalidationCapableScrollableArea.h"
 
+#include "core/frame/FrameView.h"
+#include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/html/HTMLFrameOwnerElement.h"
 #include "core/layout/LayoutBox.h"
 #include "core/layout/LayoutScrollbar.h"
 #include "core/layout/LayoutScrollbarPart.h"
 #include "core/layout/PaintInvalidationState.h"
 #include "core/paint/PaintLayer.h"
 #include "platform/graphics/GraphicsLayer.h"
 
 namespace blink {
@@ skipping 111 matching lines @@
     fullBounds.unite(m_verticalScrollbarPreviousPaintInvalidationRect);
     fullBounds.unite(m_scrollCornerAndResizerPreviousPaintInvalidationRect);
     return fullBounds;
 }
 
 void PaintInvalidationCapableScrollableArea::scrollControlWasSetNeedsPaintInvalidation()
 {
     layoutBox()->setMayNeedPaintInvalidation();
 }
 
+void PaintInvalidationCapableScrollableArea::setUserMayHaveDragged(bool dragged)
+{
+    layoutBox()->frame()->view()->setUserMayHaveDragged(dragged);
+}
+
 } // namespace blink