Vertical scrollbar width becomes zero in case of overlay scrollbar.

Source/core/rendering/RenderListBox.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  *               2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * 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.
@@ skipping 193 matching lines @@
 
     int firstIndex = select->activeSelectionStartListIndex();
     if (firstIndex >= 0 && !listIndexIsVisible(select->activeSelectionEndListIndex()))
         scrollToRevealElementAtListIndex(firstIndex);
 }
 
 void RenderListBox::computeIntrinsicLogicalWidths(LayoutUnit& minLogicalWidth, LayoutUnit& maxLogicalWidth) const
 {
     maxLogicalWidth = m_optionsWidth + 2 * optionsSpacingHorizontal;
     if (m_vBar)
-        maxLogicalWidth += m_vBar->width();
+        maxLogicalWidth += verticalScrollbarWidth();
     if (!style()->width().isPercent())
         minLogicalWidth = maxLogicalWidth;
 }
 
 void RenderListBox::computePreferredLogicalWidths()
 {
     ASSERT(!m_optionsChanged);
 
     m_minPreferredLogicalWidth = 0;
     m_maxPreferredLogicalWidth = 0;
@@ skipping 52 matching lines @@
 }
 
 int RenderListBox::baselinePosition(FontBaseline baselineType, bool firstLine, LineDirectionMode lineDirection, LinePositionMode linePositionMode) const
 {
     return RenderBox::baselinePosition(baselineType, firstLine, lineDirection, linePositionMode) - baselineAdjustment;
 }
 
 LayoutRect RenderListBox::itemBoundingBoxRect(const LayoutPoint& additionalOffset, int index)
 {
     // For RTL, items start after the left-side vertical scrollbar.
-    int scrollbarOffset = style()->shouldPlaceBlockDirectionScrollbarOnLogicalLeft() ? m_vBar->width() : 0;
+    int scrollbarOffset = style()->shouldPlaceBlockDirectionScrollbarOnLogicalLeft() ? verticalScrollbarWidth() : 0;
     return LayoutRect(additionalOffset.x() + borderLeft() + paddingLeft() + scrollbarOffset,
         additionalOffset.y() + borderTop() + paddingTop() + itemHeight() * (index - m_indexOffset),
         contentWidth(), itemHeight());
 }
 
 void RenderListBox::paintObject(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     if (style()->visibility() != VISIBLE)
         return;
 
@@ skipping 60 matching lines @@
         }
     }
 }
 
 int RenderListBox::scrollbarLeft() const
 {
     int scrollbarLeft = 0;
     if (style()->shouldPlaceBlockDirectionScrollbarOnLogicalLeft())
         scrollbarLeft = borderLeft();
     else
-        scrollbarLeft = width() - borderRight() - m_vBar->width();
+        scrollbarLeft = width() - borderRight() - verticalScrollbarWidth();
     return scrollbarLeft;
 }
 
 void RenderListBox::paintScrollbar(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     if (m_vBar) {
         IntRect scrollRect = pixelSnappedIntRect(paintOffset.x() + scrollbarLeft(),
             paintOffset.y() + borderTop(),
-            m_vBar->width(),
+            verticalScrollbarWidth(),
             height() - (borderTop() + borderBottom()));
         m_vBar->setFrameRect(scrollRect);
         m_vBar->paint(paintInfo.context, paintInfo.rect);
     }
 }
 
 static LayoutSize itemOffsetForAlignment(TextRun textRun, RenderStyle* itemStyle, Font itemFont, LayoutRect itemBoudingBox)
 {
     ETextAlign actualAlignment = itemStyle->textAlign();
     // FIXME: Firefox doesn't respect JUSTIFY. Should we?
@@ skipping 89 matching lines @@
     }
 }
 
 bool RenderListBox::isPointInOverflowControl(HitTestResult& result, const LayoutPoint& locationInContainer, const LayoutPoint& accumulatedOffset)
 {
     if (!m_vBar || !m_vBar->shouldParticipateInHitTesting())
         return false;
 
     LayoutRect vertRect(accumulatedOffset.x() + scrollbarLeft(),
                         accumulatedOffset.y() + borderTop(),
-                        m_vBar->width(),
+                        verticalScrollbarWidth(),
                         height() - borderTop() - borderBottom());
 
     if (vertRect.contains(locationInContainer)) {
         result.setScrollbar(m_vBar.get());
         return true;
     }
     return false;
 }
 
 int RenderListBox::listIndexAtOffset(const LayoutSize& offset)
 {
     if (!numItems())
         return -1;
 
     if (offset.height() < borderTop() + paddingTop() || offset.height() > height() - paddingBottom() - borderBottom())
         return -1;
 
-    int scrollbarWidth = m_vBar ? m_vBar->width() : 0;
+    int scrollbarWidth = verticalScrollbarWidth();
     int rightScrollbarOffset = style()->shouldPlaceBlockDirectionScrollbarOnLogicalLeft() ? scrollbarWidth : 0;
     int leftScrollbarOffset = style()->shouldPlaceBlockDirectionScrollbarOnLogicalLeft() ? 0 : scrollbarWidth;
     if (offset.width() < borderLeft() + paddingLeft() + rightScrollbarOffset
         || offset.width() > width() - borderRight() - paddingRight() - leftScrollbarOffset)
         return -1;
 
     int newOffset = (offset.height() - borderTop() - paddingTop()) / itemHeight() + m_indexOffset;
     return newOffset < numItems() ? newOffset : -1;
 }
 
@@ skipping 215 matching lines @@
         }
     }
 
     return true;
 }
 
 LayoutRect RenderListBox::controlClipRect(const LayoutPoint& additionalOffset) const
 {
     LayoutRect clipRect = contentBoxRect();
     if (style()->shouldPlaceBlockDirectionScrollbarOnLogicalLeft())
-        clipRect.moveBy(additionalOffset + LayoutPoint(m_vBar->width(), 0));
+        clipRect.moveBy(additionalOffset + LayoutPoint(verticalScrollbarWidth(), 0));
     else
         clipRect.moveBy(additionalOffset);
     return clipRect;
 }
 
 bool RenderListBox::isActive() const
 {
     Page* page = frame()->page();
     return page && page->focusController().isActive();
 }
@@ skipping 185 matching lines @@
 
     if (m_vBar)
         m_vBar->styleChanged();
 
     // Force an update since we know the scrollbars have changed things.
     if (document().hasAnnotatedRegions())
         document().setAnnotatedRegionsDirty(true);
 }
 
 } // namespace WebCore