Bug 818708 - Content audio channels should be muted if in background when another content audio channel is playing. r=sicking, a=bb+
Bug 825674 - Installed apps do not get affected by the hardware volume control, r=sicking, a=bb+
Bug 827773 - audio-channel-changed should contain 'none' instead 'default' when nothing is playing, r=sicking, a=bb+
Bug 819061 - [Apps] Remove workaround from Bug 813468 once Bug 815523 is done r=ferjm a=bb+