Use unsigned value with 1-bit field width, per sicking's advice. No bug.

layout/tables/nsTableFrame.h

@@ -749,7 +749,7 @@ protected:
     PRUint32 mNeedToCollapse:1;    // rows, cols that have visibility:collapse need to be collapsed
     PRUint32 mHasZeroColSpans:1;
     PRUint32 mNeedColSpanExpansion:1;
-    PRBool mResizedColumns:1;          // have we resized columns since last reflow?
+    PRUint32 mResizedColumns:1;        // have we resized columns since last reflow?
   } mBits;
 
   nsTableCellMap*         mCellMap;            // maintains the relationships between rows, cols, and cells