Use layout units in PinchViewport::scrollIntoView.

Source/core/frame/PinchViewport.cpp

 /*
  * Copyright (C) 2013 Google 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 115 matching lines @@
 {
     if (!mainFrame() || !mainFrame()->view())
         return FloatRect();
 
     FloatRect viewRect = mainFrame()->view()->visibleContentRect();
     FloatRect pinchRect = visibleRect();
     pinchRect.moveBy(viewRect.location());
     return pinchRect;
 }
 
-void PinchViewport::scrollIntoView(const FloatRect& rect)
+void PinchViewport::scrollIntoView(const LayoutRect& rect)
 {
     if (!mainFrame() || !mainFrame()->view())
         return;
 
     FrameView* view = mainFrame()->view();
 
-    float centeringOffsetX = (visibleRect().width() - rect.width()) / 2;
-    float centeringOffsetY = (visibleRect().height() - rect.height()) / 2;
+    // Snap the visible rect to layout units to match the input rect.
+    FloatRect visible = LayoutRect(visibleRect());
+
+    float centeringOffsetX = (visible.width() - rect.width()) / 2;
+    float centeringOffsetY = (visible.height() - rect.height()) / 2;
 
     DoublePoint targetOffset(
-        rect.x() - centeringOffsetX - visibleRect().x(),
-        rect.y() - centeringOffsetY - visibleRect().y());
+        rect.x() - centeringOffsetX - visible.x(),
+        rect.y() - centeringOffsetY - visible.y());
 
     view->setScrollPosition(targetOffset);
 
     DoublePoint remainder = DoublePoint(targetOffset - view->scrollPositionDouble());
     move(toFloatPoint(remainder));
 }
 
 void PinchViewport::setLocation(const FloatPoint& newLocation)
 {
     setScaleAndLocation(m_scale, newLocation);
@@ skipping 356 matching lines @@
     } else if (graphicsLayer == m_rootTransformLayer) {
         name =  "Root Transform Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace blink