Revert "Forward port SystemUI: HSPA+ Support"

This reverts commit b3f20e92fa80b153096ab86c76dfbe626ff8cb10.
Recents: Clear all button for recent apps.

An icon will appear on navbar when there are apps available to be killed on recent apps.

Credits to @BigBrother1984 for kitkat porting from jellybean

Patchset 2: Tablet mode is deprecated now, so no need of multiple callbacks
Patchset 3: Remove copyright from unaffected files
Patchset 4: Remove unused imports

Change-Id: I93d1d4cb34325190b03ae3a0d40e1bc170c92d91

Conflicts:
	core/java/android/app/StatusBarManager.java
	packages/SystemUI/src/com/android/systemui/statusbar/phone/NavigationBarView.java
Change "No recent apps" color to white instead of holo blue to follow new UI colors.

Thanks @rascarlo

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>
change-Id: Ied4730e321021445baf1191e167d645f39f4c92f