* varray.h (VARRAY_POP): Add checking variant, aborts on underflow.
	(VARRAY_TOP): Use VARRAY_CHECK so the access is bounds-checked.
	* varray.c: No need to prototype error.
	(varray_check_failed): Wrap long string onto two lines.
	(varray_underflow): New function.

From-SVN: r75786