Own Login.ConsumerNewUsersAllowed metric

Assign cmasone@chromium.org as the owner of the
Login.ConsumerNewUsersAllowed histogram.

BUG=None
TEST=None

Review URL: https://codereview.chromium.org/453723002

Cr-Commit-Position: refs/heads/master@{#288381}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@288381 0039d316-1c4b-4281-b951-d872f2087c98

tools/metrics/histograms/histograms.xml

@@ -10355,7 +10355,8 @@ Therefore, the affected-histogram name has to have at least one dot in it.
 </histogram>
 
 <histogram name="Login.ConsumerNewUsersAllowed" enum="LoginConsumerWhitelist">
-  <owner>Please list the metric's owners. Add more owner tags as needed.</owner>
+  <owner>cmasone@chromium.org</owner>
+  <owner>sumit@chromium.org</owner>
   <summary>
     Chrome OS histogram tracking, per consumer sign-in, whether the device owner
     is allowing arbitrary accounts to be used on the device, or only those on a