OWNERS: Prefer Jeff Sharkey's @android.com account over @google.com

He prefers to use his @android.com account.

Test: Treehugger
Bug: 63673347
Exempt-From-Owner-Approval: Allow @android.com to approve this CL :)

Change-Id: Ie80cc7864de7b91ae44ad57f0bae9b859d034803