Additional fix on top of roc's patch for bug 421069 to fix the regression it caused. r=dholbert approval1.9b5=damon

layout/reftests/bugs/reftest.list

@@ -765,8 +765,8 @@ fails == 413027-3.html 413027-3-ref.html
 == 420069-1.html 420069-1-ref.html
 == 420069-2.html 420069-2-ref.html
 == 420351-1.html 420351-1-ref.html
-fails == 421069.html 421069-ref.html # bug 421069
-fails == 421069.html 421069-ref2.html # bug 421069
+== 421069.html 421069-ref.html
+== 421069.html 421069-ref2.html
 == 421069-ref.html 421069-ref2.html
 == 421234-1.html 421234-1-ref.html
 == 421419-1.html 421419-1-ref.html

layout/tables/nsTablePainter.cpp

@@ -584,10 +584,9 @@ TableBackgroundPainter::PaintRow(nsTableRowFrame* aFrame,
   //else: Use row group's coord system -> no translation necessary
 
   for (nsTableCellFrame* cell = aFrame->GetFirstCell(); cell; cell = cell->GetNextCell()) {
-    mCellRect = cell->GetRect();
     //Translate to use the same coord system as mRow.
-    mCellRect.MoveBy(mRow.mRect.x, mRow.mRect.y);
-    if (mCellRect.Intersects(mDirtyRect - mRenderPt)) {
+    mCellRect = cell->GetRect() + mRow.mRect.TopLeft() + mRenderPt;
+    if (mCellRect.Intersects(mDirtyRect)) {
       nsresult rv = PaintCell(cell, aPassThrough || cell->IsPseudoStackingContextFromStyle());
       if (NS_FAILED(rv)) return rv;
     }
@@ -656,7 +655,7 @@ TableBackgroundPainter::PaintCell(nsTableCellFrame* aCell,
   //Paint cell background in border-collapse unless we're just passing
   if (mIsBorderCollapse && !aPassSelf) {
     aCell->PaintCellBackground(mRenderingContext, mDirtyRect,
-            mRenderPt + mCellRect.TopLeft());
+                               mCellRect.TopLeft());
   }
 
   return NS_OK;