fixed 3 dumb bugs I introduced recently.

1. cellmap couldn't properly delete CellData because definition was unavailable
2. optimized table cells made taller wouldn't shrink when they should because we were not
remembering the previous desired height of the cell.
3. rows were placing cells on the left edge, and not adding in the left margin.

layout/tables/nsTableCellFrame.cpp

@@ -60,6 +60,8 @@ nsTableCellFrame::nsTableCellFrame(nsIContent* aContent,
   mColSpan=1;
   mColIndex=0;
   mPriorAvailWidth=0;
+  mPriorDesiredSize.width=0;
+  mPriorDesiredSize.height=0;
 }
 
 nsTableCellFrame::~nsTableCellFrame()
@@ -289,6 +291,7 @@ NS_METHOD nsTableCellFrame::Reflow(nsIPresContext* aPresContext,
   mFirstChild->WillReflow(*aPresContext);
   mFirstChild->MoveTo(leftInset, topInset);
   aStatus = ReflowChild(mFirstChild, aPresContext, kidSize, kidReflowState);
+  SetPriorDesiredSize(kidSize);
 
   if (PR_TRUE==gsDebug || PR_TRUE==gsDebugNT)
   {