Merge pull request #15711 from steveck-chung/DSDS-sim_switch_for_MMS

Bug 961938 - [DSDS][MMS] Switching data confirmation message will pop up twice r=julien
(cherry picked from commit 9497e89bbf6060d1a837a7ccbf396f8c359eb13b)

Conflicts:
	apps/sms/test/unit/thread_ui_test.js
Merge pull request #15874 from Rik/simslot-965155

Bug 965155 - SIM manager will set all outgoing settings to SIM 2 after r... r=etienne
(cherry picked from commit 0cb3631191ef12947e981c0ff35e9d27256972cf)
Bug 961938 - follow-up gjslint fix r=me
Merge pull request #15653 from dominickuo/bug-946556

Bug 946556 - [Music] Disable the play controls when using a bluetooth headset in a call, r=jimporter(cherry picked from commit 0646bf911164ca9e2f80a6b703558bed35b449b2)

Conflicts:

	apps/music/index.html