DocumentsUI: fix white action context bar in TRDS tablet view

Change-Id: I3c580a2aa4f8abbcfd06ad974518343f6e9190c5
Floating window: Fix possible NPE

Avoid possible NPE if app provides no interface such as pushbullet's
test notification & other apps which provide one.

Change-Id: I35c13959296a56e44f21f1aee0a736e7f786aa57

Conflicts:
	packages/SystemUI/res/values/cm_strings.xml
	packages/SystemUI/src/com/android/systemui/statusbar/BaseStatusBar.java