bug 553972 - split row groups only if the available height isconstrained r=roc

layout/tables/nsTableRowGroupFrame.cpp

@@ -1324,9 +1324,9 @@ nsTableRowGroupFrame::Reflow(nsPresContext*           aPresContext,
   // See if all the frames fit. Do not try to split anything if we're
   // not paginated ... we can't split across columns yet.
   if (aReflowState.mFlags.mTableIsSplittable &&
+      NS_UNCONSTRAINEDSIZE != aReflowState.availableHeight &&
       (NS_FRAME_NOT_COMPLETE == aStatus || splitDueToPageBreak || 
-       (NS_UNCONSTRAINEDSIZE != aReflowState.availableHeight &&
-       aDesiredSize.height > aReflowState.availableHeight))) {
+       aDesiredSize.height > aReflowState.availableHeight)) {
     // Nope, find a place to split the row group 
     PRBool specialReflow = (PRBool)aReflowState.mFlags.mSpecialHeightReflow;
     ((nsHTMLReflowState::ReflowStateFlags&)aReflowState.mFlags).mSpecialHeightReflow = PR_FALSE;