Allow unit tests to include or exclude test sets.

Allow unit tests to include or exclude test sets.

This modifies the command line to take test
matches of the form:

   --match [or -m] [~][^]match[$] [~][^]match[$] ...

   ~ causes a matching test to always be skipped

   ^ requires the start of the test to match

   $ requires the end of the test to match

   ^ and $ requires an exact match


If a test does not match any list entry,
it is skipped unless some list entry starts with ~
Committed: https://code.google.com/p/skia/source/detail?r=8955

[bsalomon, 2013-04-30 17:35:31]

lgtm, but maybe the help text should be updated? Line 143 in my version:

DEFINE_string2(match, m, NULL, "substring of test name to run.");

[caryclark, 2013-05-02 13:14:44]

Committed patchset #1 manually as r8955 (presubmit successful).