Can now adjust the number of retries before the blacklist is disabled.
Also added UMA recording of the blacklist disabled and retry succeeded events.
Deprecating the blacklist start up events 'BLACKLIST_THUNK_SETUP_FAILED' and
'BLACKLIST_INTERCEPTION_FAILED' as we are switching over to a more coarse
grained recording of the set up status (this information can be gathered from
crash reporting now anyways).
BUG=
Review URL: https://codereview.chromium.org/
311893005
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@277614 0039d316-1c4b-4281-b951-d872f2087c98