Enable toast for 597....

Enable toast for 597.

1. Merge r69465: Enable Japanese inactive user toast experiments.
2. Merge r69835: Fixes update step to not clobber client code setting if toast experiment is not active.
3. Change experiment_enabled to true
4. Remove the en_US exeriment, enable experiment for ja
5. For locale != ja, use message flavor 2, "There's a new, safer version of Chrome available." 
6. Change client codes to a new namespace for the Japan experiment (S{JKLM}xx)

R= cpu, gwilson
BUG= none
TOAST= yeah!



Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=73572

[Mark Larson, 2011-02-02 21:19:07]

Toast changes for 597 are ready for review. I've already gone over this
face-to-face with Glenn. 

I'll check in on the branch, and it will just go out with whatever the next
update after that is.

[Mark Larson, 2011-02-03 00:37:43]

Oops. Sent out a "please review" email without adding any actual reviewers...

[cpu_(ooo_6.6-7.5), 2011-02-03 00:44:51]

lgtm