[patch] Add asserts to {decrement,increment}_reading_symtab

[Tom Tromey]

>>>>> "Doug" == Doug Evans <dje@google.com> writes:

Doug> I will check this in in a few days if there are no objections.
Doug> Regression tested on amd64-linux.

Doug> 2013-05-07  Doug Evans  <dje@google.com>

Doug> 	* symfile.c (decrement_reading_symtab): Add assert.
Doug> 	(increment_reading_symtab): Ditto.

Looks good to me.

Tom