Round visual rects when crossing frame boundaries.

third_party/WebKit/Source/core/paint/PartPainter.cpp

Index: third_party/WebKit/Source/core/paint/PartPainter.cpp
diff --git a/third_party/WebKit/Source/core/paint/PartPainter.cpp b/third_party/WebKit/Source/core/paint/PartPainter.cpp
index 9df9f9a1e81d6d31693d1d4f9e00f053fed7c12f..121f43828f806cfcc95debd372865ebc925e74bd 100644
--- a/third_party/WebKit/Source/core/paint/PartPainter.cpp
+++ b/third_party/WebKit/Source/core/paint/PartPainter.cpp
@@ -105,8 +105,7 @@ void PartPainter::paintContents(const PaintInfo& paintInfo, const LayoutPoint& p
     // Tell the widget to paint now. This is the only time the widget is allowed
     // to paint itself. That way it will composite properly with z-indexed layers.
     IntPoint widgetLocation = widget->frameRect().location();
-    IntPoint paintLocation(roundToInt(adjustedPaintOffset.x() + m_layoutPart.borderLeft() + m_layoutPart.paddingLeft()),
-        roundToInt(adjustedPaintOffset.y() + m_layoutPart.borderTop() + m_layoutPart.paddingTop()));
+    IntPoint paintLocation(roundedIntPoint(adjustedPaintOffset + m_layoutPart.contentBoxOffset()));
 
     IntSize widgetPaintOffset = paintLocation - widgetLocation;
     // When painting widgets into compositing layers, tx and ty are relative to the enclosing compositing layer,