Refactor SyncBuildAndRunRevision to remove deep nesting.

Refactor SyncBuildAndRunRevision to remove deep nesting.

I also propose to rename this function to just RunTest, because its purpose is to do everything necessary to obtain a build and run a test to get results, and it's a relatively important and high-level function.

"Flat is better than nested."
  -- The Zen of Python, PEP 20.

BUG=

Committed: https://crrev.com/01aea5538cc28f44485c6b3211c39cb49f758f26
Cr-Commit-Position: refs/heads/master@{#292661}

[tonyg, 2014-08-18 16:36:16]

Please get a green bisect run w/ this patch and then lgtm

[qyearsley, 2014-08-29 16:19:18]

On 2014/08/18 16:36:16, tonyg wrote:
> Please get a green bisect run w/ this patch and then lgtm

Finally a green bisect run :-)

[qyearsley, 2014-08-29 16:19:20]

The CQ bit was checked by qyearsley@chromium.org

[commit-bot: I haz the power, 2014-08-29 16:19:55]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/qyearsley@chromium.org/484583002/260001

[commit-bot: I haz the power, 2014-08-29 17:16:56]

Committed patchset #14 (id:260001) as 71e8ac4a2037c217484db8ce393267ff43a33e46

[commit-bot: I haz the power, 2014-09-10 03:09:46]

Patchset 14 (id:??) landed as
https://crrev.com/01aea5538cc28f44485c6b3211c39cb49f758f26
Cr-Commit-Position: refs/heads/master@{#292661}