Increased the unresponsive threshold from 6 to 12 in beta

Increased the unresponsive_threshold from 6 to 12
in Beta channel and XP. We will crash the browser
if UI/IO threads don't respond within 24 secs
(instead of 12 secs) in Beta channel and Windows XP.

BUG=90095
R=jar
TEST=thread_watcher unit tests

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=98697

[ramant (doing other things), 2011-08-25 16:33:58]

Hi Jim,
  As we had talked last night, doubled the unresponsive number of seconds (from
12 to 24 secs). For XP, increased the unresponsive number of seconds to 48.
Would appreciate your comments.

thanks,
raman

[jar (doing other things), 2011-08-29 18:13:40]

LGTM

[commit-bot: I haz the power, 2011-08-29 21:03:49]

Change committed as 98697