Tag mobile web edits more explicitly

This makes it easier to differentiate between mobile web
edits and mobile app edits, while also having a tag
for 'all' mobile edits.

Change-Id: I7bc29cc5dad7a39a006c212a23af56b1b3f7ed58
(cherry picked from commit af312575773f790b098fbf3211c70985cb3a0de0)