Support subpixel layout for borders.

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

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 121 matching lines @@
   return ScrollbarTheme::theme().scrollbarThickness();
 }
 
 void LayoutScrollbarPart::computeScrollbarWidth() {
   if (!m_scrollbar->styleSource())
     return;
   // FIXME: We are querying layout information but nothing guarantees that it's
   // up to date, especially since we are called at style change.
   // FIXME: Querying the style's border information doesn't work on table cells
   // with collapsing borders.
-  int visibleSize = (m_scrollbar->styleSource()->size().width() -
-                     m_scrollbar->styleSource()->style()->borderLeftWidth() -
-                     m_scrollbar->styleSource()->style()->borderRightWidth())
-                        .toInt();
+  int visibleSize = m_scrollbar->styleSource()->size().width() -
+                    m_scrollbar->styleSource()->style()->borderLeftWidth() -
+                    m_scrollbar->styleSource()->style()->borderRightWidth();
   int w = calcScrollbarThicknessUsing(MainOrPreferredSize, style()->width(),
                                       visibleSize);
   int minWidth =
       calcScrollbarThicknessUsing(MinSize, style()->minWidth(), visibleSize);
   int maxWidth = style()->maxWidth().isMaxSizeNone()
                      ? w
                      : calcScrollbarThicknessUsing(MaxSize, style()->maxWidth(),
                                                    visibleSize);
   setWidth(LayoutUnit(std::max(minWidth, std::min(maxWidth, w))));
 
   // Buttons and track pieces can all have margins along the axis of the
   // scrollbar.
   setMarginLeft(
       minimumValueForLength(style()->marginLeft(), LayoutUnit(visibleSize)));
   setMarginRight(
       minimumValueForLength(style()->marginRight(), LayoutUnit(visibleSize)));
 }
 
 void LayoutScrollbarPart::computeScrollbarHeight() {
   if (!m_scrollbar->styleSource())
     return;
   // FIXME: We are querying layout information but nothing guarantees that it's
   // up to date, especially since we are called at style change.
   // FIXME: Querying the style's border information doesn't work on table cells
   // with collapsing borders.
-  int visibleSize = (m_scrollbar->styleSource()->size().height() -
-                     m_scrollbar->styleSource()->style()->borderTopWidth() -
-                     m_scrollbar->styleSource()->style()->borderBottomWidth())
-                        .toInt();
+  int visibleSize = m_scrollbar->styleSource()->size().height() -
+                    m_scrollbar->styleSource()->style()->borderTopWidth() -
+                    m_scrollbar->styleSource()->style()->borderBottomWidth();
   int h = calcScrollbarThicknessUsing(MainOrPreferredSize, style()->height(),
                                       visibleSize);
   int minHeight =
       calcScrollbarThicknessUsing(MinSize, style()->minHeight(), visibleSize);
   int maxHeight = style()->maxHeight().isMaxSizeNone()
                       ? h
                       : calcScrollbarThicknessUsing(
                             MaxSize, style()->maxHeight(), visibleSize);
   setHeight(LayoutUnit(std::max(minHeight, std::min(maxHeight, h))));
 
@@ skipping 60 matching lines @@
   m_scrollableArea->setScrollCornerNeedsPaintInvalidation();
 }
 
 LayoutRect LayoutScrollbarPart::visualRect() const {
   // This returns the combined bounds of all scrollbar parts, which is
   // sufficient for correctness but not as tight as it could be.
   return m_scrollableArea->visualRectForScrollbarParts();
 }
 
 }  // namespace blink