Phone: Sprint MWI Quirk: Phantom message wait indicator workaround (2/2)

Part (1/2) http://gerrit.sudoservers.com/#/c/5235/

PatchSet 1: Initial commit
PatchSet 2: Fix commit message

Change-Id: Iec65915475e6b8224b82feec5571f7bbded0545a
Merge remote-tracking branch 'upstream/jb-mr1' into jb-mr1