Add infrastructure for skipping tests in GC stress mode.

Add infrastructure for skipping tests in GC stress mode.

Also move the GC stress configuration from the buildbot to the test runner.

BUG=
R=jkummerow@chromium.org, mvstanton@chromium.org

Committed: https://code.google.com/p/v8/source/detail?r=18708

[Michael Achenbach, 2014-01-21 11:30:53]

PTAL, Jakob at the test runner and Michael at the skipped tests...

[mvstanton, 2014-01-21 11:58:34]

lgtm, one small nit.

https://codereview.chromium.org/141653008/diff/1/test/mjsunit/elements-kind.js
File test/mjsunit/elements-kind.js (left):

https://codereview.chromium.org/141653008/diff/1/test/mjsunit/elements-kind.j...
test/mjsunit/elements-kind.js:29: // Flags: --nostress-opt --nostress-compaction
--gc-interval=-1
You could probably remove --nostress-compaction here too.

[Michael Achenbach, 2014-01-21 12:10:29]

https://codereview.chromium.org/141653008/diff/1/test/mjsunit/elements-kind.js
File test/mjsunit/elements-kind.js (left):

https://codereview.chromium.org/141653008/diff/1/test/mjsunit/elements-kind.j...
test/mjsunit/elements-kind.js:29: // Flags: --nostress-opt --nostress-compaction
--gc-interval=-1
On 2014/01/21 11:58:35, mvstanton wrote:
> You could probably remove --nostress-compaction here too.

Done.

[Jakob Kummerow, 2014-01-21 12:29:56]

Yay! Having --gc-stress as a flag for run-tests.py is a most welcome improvement
for local testing.

LGTM.

[Michael Achenbach, 2014-01-21 12:41:40]

Committed patchset #2 manually as r18708 (tree was closed).