Frameworks: Actually start to use HEADS_UP_REQUESTED extra

Prepairing slim heads up feature, we do this here to allow apps to
send a heads up notification no matter what.

Google introduced this flag but is not using it in the actual API

Take HEADS_UP_REQUESTED into account to indicate that this notification
is a good heads up candidate.

How to use it you can see in email or mms app

Change-Id: I4a29404122ae12ab9b95e1d223911078a360b44e
SystemUI: Ensure that the Clock is actually enabled in IconMerger

to device if we need to calculate

Change-Id: If12b0e26b32f044f1a82cf8b539283194d1d0b4c
Forward Port: Volume button seek on screen off [1/2]

PS : Fix the short press event type
Framework: StatusBar Ticker (1/2)
[1/2] Base: Hide power menu on lockscreen

Adds an option to enable/disable power menu on lockscreen.
policy: only disable power menu on secure lock screen