[Slimming Paint] Adjust the paint rect for paintOffset when painting column rules.

Source/core/paint/MultiColumnSetPainter.cpp

Index: Source/core/paint/MultiColumnSetPainter.cpp
diff --git a/Source/core/paint/MultiColumnSetPainter.cpp b/Source/core/paint/MultiColumnSetPainter.cpp
index 75ab03962acbda51659682867106b24077b772b7..a326c1f82511c3bd001f56c916491f589d6080b9 100644
--- a/Source/core/paint/MultiColumnSetPainter.cpp
+++ b/Source/core/paint/MultiColumnSetPainter.cpp
@@ -51,7 +51,9 @@ void MultiColumnSetPainter::paintColumnRules(const PaintInfo& paintInfo, const L
     if (colCount <= 1)
         return;
 
-    RenderDrawingRecorder drawingRecorder(paintInfo.context, m_renderMultiColumnSet, DisplayItem::ColumnRules, m_renderMultiColumnSet.visualOverflowRect());
+    LayoutRect paintRect = m_renderMultiColumnSet.visualOverflowRect();
+    paintRect.moveBy(paintOffset);
+    RenderDrawingRecorder drawingRecorder(paintInfo.context, m_renderMultiColumnSet, DisplayItem::ColumnRules, paintRect);
     if (drawingRecorder.canUseCachedDrawing())
         return;