Merge pull request #16982 from steveck-chung/bug-973007

Bug 973007 - [B2G] [Messaging] Keyboard appears when accessing the contact list from the compose message screen. r=julienw
Merge pull request #16964 from dominickuo/bug-973156-new-2

Bug 973156 - [Music] Send mozinterruptbegin and mozinterruptend to system for show/hide the media playback widget, r=jimporter(cherry picked from commit b83a79969718ea189cdc5cfa55d40fee38c11cb6)

Conflicts:

	apps/system/test/marionette/media_playback_test.js