SystemUI: Fix potential NPE

Does already cause issues on some Halo ports to other ROMs.
Might not cause issues on PA (yet), but better safe than sorry.
Allow multiple emulated storages at the same time.

Only do multiuser mapping for primary emulated storage as per google docs.
Allow all non-primary emulated storage to have id other than 0 so that
it could be distinguished from the primary volume.

Change-Id: I7b70b9067fd6211055fb9074710f48107d7b0e8e
T-Mobile required login tethering fix
ScreenShot QuickTrash
Notification long press fix
Allow theming of lockscreen

Change-Id: I10799482e0b393746b4c9818f94862109fac6006
Voice+: Missing Strings
HALO Mods (1/2)
    * Animation Controls (options)
    * Long press status info

[part 2 in android_packages_apps_Settings]