Report success to Omaha when binaries are uninstalled.

Although the process exit code is 0 in this case, I forgot to update the
registry for reporting's sake. Oops.

BUG=309078
R=robertshield@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/29553003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229646 0039d316-1c4b-4281-b951-d872f2087c98
Use primary instead of first_display_id ,
which may be invalid, to check docked mode

 I still not sure how the bug can happen, but this is
probably better. 

BUG=279484

Review URL: https://codereview.chromium.org/29823004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@229647 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 229647