Backed out changeset 26c7b580d5a2 (bug 622507) due to orange. a=backout

layout/xul/base/src/nsMenuPopupFrame.cpp

@@ -1273,10 +1273,6 @@ nsMenuPopupFrame::SetPopupPosition(nsIFrame* aAnchorFrame, PRBool aIsMove)
                               screenRect.YMost(), anchorRect.y, anchorRect.YMost(),
                               margin.top, margin.bottom, offsetForContextMenu, vFlip, &mVFlip);
 
-  // snap the screen position to device pixels, see bug 622507
-  screenPoint.x = presContext->RoundAppUnitsToNearestDevPixels(screenPoint.x);
-  screenPoint.y = presContext->RoundAppUnitsToNearestDevPixels(screenPoint.y);
-
   NS_ASSERTION(screenPoint.x >= screenRect.x && screenPoint.y >= screenRect.y &&
                screenPoint.x + mRect.width <= screenRect.XMost() &&
                screenPoint.y + mRect.height <= screenRect.YMost(),