Bug 910446: Handle duration changes in Music app

With the landing of bug 831224, the duration of MP3 files is
computed while they are playing, and updated accordingly. If
this happens, we distribute a 'durationchange' event to the
related apps.

With this patch, we handle 'durationchange' in the Music app.
All we have to do is to update the displayed duration and ensure
that the end timeout triggers at the end of the track.

Signed-off-by: Thomas Zimmermann <tdz@users.sourceforge.net>
Bug 900870 - Register to onpairedstatuschanged and remove bluetooth-pairedstatuschanged system message
Bug 825913 - Integrate code coverage library in the test agent
Bug 911709 - [MMS] missing l10n entity
Bug 912060 - Better and more tested call screen toggling
Bug 912184: use require() to load shared/js files
Bug 909374 - [Video] Improve view activity saving feature robustness
Bug 911669 - [B2G][Helix][Camera][ouyangming] The flash's state is different between the android device when do the same operation
Bug 902497 - [sms][mms] use the new asynchronous getSegmentInfoText from bug 903403 for updateSmsSegmentLimit r=schung

* we don't call getSegmentInfoForText more than once every 500ms
* getSegmentInfoForText is now asynchronous and the new code is handling this
* we now do the composeForm dataset type change in ThreadUI. As a result, the
  "type" event, sent by Compose, is not cancelable anymore, because we don't use
  this anymore.
Bug 911809 - Copy variant.json at build-time to ftu. r=yurenju
Bug 907941 - gaia-ui-tests-pushbot (see bug)
Bug 901227 - APN Settings authType field typo error leads to data call error. r=arthurcc
Bug 907941 - gaia-ui-tests-pushbot (see bug)
Bug 907941 - gaia-ui-tests-pushbot (see bug)
Merge pull request #11924 from jaoo/901227

Bug 901227 - APN Settings authType field typo error leads to data call error. r=arthurcc
Merge pull request #11909 from etiennesegonzac/bug-912060-call-screen-exit-cleanup-and-fix

Bug 912060 - Better and more tested call screen toggling
Bug 907941 - gaia-ui-tests-pushbot (see bug)
Bug 912490 - Adding a css class to handledCall nodes to make them easier
to target from marionette tests.
Merge pull request #11926 from etiennesegonzac/bug-912490-call-for-test-selectors

Bug 912490 - Adding a css class to handledCall nodes to make them easier to target from marionette tests. r=rik
Revert "Bug 891743 - Add voice privacy mode for CDMA"

This reverts commit c5cd9baaef9aef54a724e264005f56d98c93ec0e.