Use float for scroll offset.

third_party/WebKit/Source/core/layout/PaintInvalidationState.cpp

 // Copyright 2014 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/layout/PaintInvalidationState.h"
 
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/layout/LayoutInline.h"
@@ skipping 330 matching lines @@
   if (!m_cachedOffsetsEnabled)
     return;
 
   if (!m_currentObject.isBox())
     return;
   const LayoutBox& box = toLayoutBox(m_currentObject);
 
   if (box.isLayoutView()) {
     if (!RuntimeEnabledFeatures::rootLayerScrollingEnabled()) {
       if (box != m_paintInvalidationContainer) {
-        m_paintOffset -= toLayoutView(box).frameView()->scrollOffset();
+        m_paintOffset -=
+            LayoutSize(toLayoutView(box).frameView()->scrollOffset());
         addClipRectRelativeToPaintOffset(toLayoutView(box).viewRect());
       }
       return;
     }
   } else if (box.isSVGRoot()) {
     const LayoutSVGRoot& svgRoot = toLayoutSVGRoot(box);
     if (svgRoot.shouldApplyViewportClip())
       addClipRectRelativeToPaintOffset(
           LayoutRect(LayoutPoint(), LayoutSize(svgRoot.pixelSnappedSize())));
   } else if (box.isTableRow()) {
@@ skipping 248 matching lines @@
 }
 
 void PaintInvalidatorContextAdapter::mapLocalRectToPaintInvalidationBacking(
     const LayoutObject& object,
     LayoutRect& rect) const {
   DCHECK(&object == &m_paintInvalidationState.currentObject());
   m_paintInvalidationState.mapLocalRectToPaintInvalidationBacking(rect);
 }
 
 }  // namespace blink