[Element / Autofill] Add boundsInViewportFloat() to fix <input> popup misalignment.

third_party/WebKit/Source/platform/scroll/Scrollbar.cpp

 /*
  * Copyright (C) 2004, 2006, 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 516 matching lines @@
 }
 
 IntRect Scrollbar::convertFromContainingWidget(const IntRect& parentRect) const
 {
     if (m_scrollableArea)
         return m_scrollableArea->convertFromContainingWidgetToScrollbar(this, parentRect);
 
     return Widget::convertFromContainingWidget(parentRect);
 }
 
+FloatRect Scrollbar::convertToContainingWidget(const FloatRect& localRect) const
+{
+    if (m_scrollableArea)
+        return m_scrollableArea->convertFromScrollbarToContainingWidget(this, localRect);
+
+    return Widget::convertToContainingWidget(localRect);
+}
+
 IntPoint Scrollbar::convertToContainingWidget(const IntPoint& localPoint) const
 {
     if (m_scrollableArea)
         return m_scrollableArea->convertFromScrollbarToContainingWidget(this, localPoint);
 
     return Widget::convertToContainingWidget(localPoint);
 }
 
 IntPoint Scrollbar::convertFromContainingWidget(const IntPoint& parentPoint) const
 {
@@ skipping 18 matching lines @@
 {
     if (m_theme->shouldRepaintAllPartsOnInvalidation()) {
         m_trackNeedsRepaint = true;
         m_thumbNeedsRepaint = true;
     }
     if (m_scrollableArea)
         m_scrollableArea->setScrollbarNeedsPaintInvalidation(this);
 }
 
 } // namespace blink