Use float for scroll offset.

third_party/WebKit/Source/core/paint/PaintPropertyTreeBuilder.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/PaintPropertyTreeBuilder.h"
 
 #include "core/frame/FrameView.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Settings.h"
 #include "core/layout/LayoutInline.h"
@@ skipping 151 matching lines @@
   frameTranslate.translate(frameView.x() + context.current.paintOffset.x(),
                            frameView.y() + context.current.paintOffset.y());
   createOrUpdateFrameViewPreTranslation(frameView, context.current.transform,
                                         frameTranslate, FloatPoint3D());
 
   FloatRoundedRect contentClip(
       IntRect(IntPoint(), frameView.visibleContentSize()));
   createOrUpdateFrameViewContentClip(frameView, context.current.clip,
                                      frameView.preTranslation(), contentClip);
 
-  DoubleSize scrollOffset = frameView.scrollOffsetDouble();
+  ScrollOffset scrollOffset = frameView.scrollOffset();
   if (frameView.isScrollable() || !scrollOffset.isZero()) {
     TransformationMatrix frameScroll;
     frameScroll.translate(-scrollOffset.width(), -scrollOffset.height());
     createOrUpdateFrameViewScrollTranslation(
         frameView, frameView.preTranslation(), frameScroll, FloatPoint3D());
 
     IntSize scrollClip = frameView.visibleContentSize();
     IntSize scrollBounds = frameView.contentsSize();
     bool userScrollableHorizontal =
         frameView.userInputScrollable(HorizontalScrollbar);
@@ skipping 378 matching lines @@
   context.current.shouldFlattenInheritedTransform = false;
   context.current.renderingContextID = 0;
 }
 
 void PaintPropertyTreeBuilder::updateScrollAndScrollTranslation(
     const LayoutObject& object,
     PaintPropertyTreeBuilderContext& context) {
   if (object.hasOverflowClip()) {
     const LayoutBox& box = toLayoutBox(object);
     const PaintLayerScrollableArea* scrollableArea = box.getScrollableArea();
-    DoubleSize scrollOffset = box.scrolledContentOffset();
+    IntSize scrollOffset = box.scrolledContentOffset();
     if (!scrollOffset.isZero() || scrollableArea->scrollsOverflow()) {
       TransformationMatrix matrix = TransformationMatrix().translate(
           -scrollOffset.width(), -scrollOffset.height());
       context.current.transform =
           object.getMutableForPainting()
               .ensureObjectPaintProperties()
               .createOrUpdateScrollTranslation(
                   context.current.transform, matrix, FloatPoint3D(),
                   context.current.shouldFlattenInheritedTransform,
                   context.current.renderingContextID);
@@ skipping 161 matching lines @@
     return;
 
   updateOverflowClip(object, context);
   updatePerspective(object, context);
   updateSvgLocalToBorderBoxTransform(object, context);
   updateScrollAndScrollTranslation(object, context);
   updateOutOfFlowContext(object, context);
 }
 
 }  // namespace blink