Reload the web-app if an IT2Me connection fails.

The underlying cause of the referenced bug is that when I refactored the
WCS code, I didn't support multiple calls to start(), thinking they were
never needed because we always reload the web-app when a connection closes.
Unfortunately, this misses the case of failed IT2Me connections where we
previously returned the user to the access code entry screen to try again.

This CL makes the IT2Me and Me2Me modes the same by reloading the web-app
in both cases. This introduces a small regression insofar as mistyping an
access code now means an extra reload and button click before trying again.
LMK if you think this is unacceptable--I need to implement a cleaner flow
for Apps v2 anyway, but that's likely to be unsuitable for merging to M26.

BUG=175494


Review URL: https://chromiumcodereview.appspot.com/12258030

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@182742 0039d316-1c4b-4281-b951-d872f2087c98