Add automatic retry mechanism and LKGR support.

Add automatic retry mechanism and LKGR support.

Add code to determine good revision per builder and fallback to LKGR when all
hope is lost. This required rewriting StepDb (yet) again.

The retry mechanism special cases update and compile steps.

Remove thirdparty since SortedDict is not necessary anymore.

R=dpranke@chromium.org
BUG=
TEST=Lots

ABANDONNED

[M-A Ruel, 2011-06-08 13:40:54]

I haven't live tested yet, I've focused on writing unit tests instead.

[Dirk Pranke, 2011-06-08 22:49:49]

A couple of nits, but frankly I've lost the bigger picture.

What was the logic being done before, and what are you doing now? Why are we
retrying against LKGR and what will we do with the result? Why didn't the
previous thing work?

http://codereview.chromium.org/7108020/diff/1/tests/try_server_test.py
File tests/try_server_test.py (right):

http://codereview.chromium.org/7108020/diff/1/tests/try_server_test.py#newcod...
tests/try_server_test.py:197: def step_result(self, builder, name, result):
maybe rename this to 'set_step_result' if you renamed the other to
'set_build_result' in the last change? The names should be similar, at least.

[Dirk Pranke, 2011-06-08 23:51:00]

LGTM once you address the nits (one way or another). I'll take the "bigger
picture" question off-thread.

[M-A Ruel, 2011-06-09 16:10:20]

There is an issue with this change, since update_status() doesn't have the patch
applied, the job was sent without a patch. I'll split it in parts, closing in
the meantime.