Implement next alarm info in expanded QS.

Also make the representation of alarm on lockscreen consistent with
QS. In addition, fix a bug where pending app transition was overriden
to make the alarm click interaction look nice.

Bug: 15392951
Bug: 15856205
Change-Id: Iacdf6a38c5c1a7484b4b328c9a3fa4d25e071c64