Add tests that backtrace and backtrace_symbols produce correct results

[Andreas Schwab]

"Joseph S. Myers" <joseph@codesourcery.com> writes:

> This code should not be called for the do_test frame; if it is, you have 
> some other problem with the frames before do_test.  The code deliberately 
> does not check for a function name for the do_test frame.

But do_test isn't the outermost frame.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."