Use float for scroll offset.

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

Index: third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp b/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
index cffaf0d24ea409cc3423146e11ba1fe9b875bf26..3eb01b31a6449a51181b1136656ad0ef2ac29c8b 100644
--- a/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutBoxModelObject.cpp
@@ -784,10 +784,10 @@ void LayoutBoxModelObject::updateStickyPositionConstraints() const {
     // The sticky position constraint rects should be independent of the current scroll position, so after
     // mapping we add in the scroll position to get the container's position within the ancestor scroller's
     // unscrolled layout overflow.
-    FloatSize scrollOffset(
+    ScrollOffset scrollOffset(
         scrollAncestor
             ? toFloatSize(
-                  scrollAncestor->getScrollableArea()->offsetFromOrigin())
+                  scrollAncestor->getScrollableArea()->absolutePosition())
             : FloatSize());
     scrollContainerRelativePaddingBoxRect.move(scrollOffset);
   }
@@ -908,7 +908,7 @@ FloatRect LayoutBoxModelObject::computeStickyConstrainingRect() const {
   FloatRect constrainingRect;
   constrainingRect =
       FloatRect(enclosingClippingBox->overflowClipRect(LayoutPoint(DoublePoint(
-          enclosingClippingBox->getScrollableArea()->offsetFromOrigin()))));
+          enclosingClippingBox->getScrollableArea()->absolutePosition()))));
   constrainingRect.move(enclosingClippingBox->paddingLeft(),
                         enclosingClippingBox->paddingTop());
   constrainingRect.contract(