[Telemetry] fix google_credentials_backend_unittest.py and facebook_credentials_backend_unittest.py.

[Telemetry] fix google_credentials_backend_unittest.py and facebook_credentials_backend_unittest.py.

The mentioned files both have flaky tests called testRealLoginWithDontOverrideProfileIfPossible.
This should fix them.

BUG=169447
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=177266

[nduca, 2013-01-14 20:59:27]

message: The only real clean option I see here if you restart the browser is to
change browser_options.dont_override_profile to be tristate:
1. use_clean_profile [default]
2. profile_dir
3. default profile

This is a hefty amount of work for just a test.

What about forcing the browser_credentials system to think that needs to login
again? E.g. tell it to login, then calling a private-ish method to say "forget
everythign you know" then log in again?

[hartmanng, 2013-01-15 18:59:51]

> What about forcing the browser_credentials system to think that needs to login
> again? E.g. tell it to login, then calling a private-ish method to say "forget
> everythign you know" then log in again?

SGTM, how does this look?

[nduca, 2013-01-16 03:02:07]

seems cool. lgtm but I didn't really exhaustively review. Can you get dtu to
give it a quick once over?

[hartmanng, 2013-01-16 14:09:58]

On 2013/01/16 03:02:07, nduca wrote:
> seems cool. lgtm but I didn't really exhaustively review. Can you get dtu to
> give it a quick once over?

sure thing.
dtu, please take a look.

[dtu, 2013-01-16 20:22:56]

lgtm

[hartmanng, 2013-01-16 20:28:05]

thanks!

[commit-bot: I haz the power, 2013-01-16 20:30:18]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/hartmanng@chromium.org/11875017/2001

[commit-bot: I haz the power, 2013-01-16 23:36:53]

Change committed as 177266