Recents: force clear caches on longclick

PS1: don't forget to keep locked app there

Change-Id: Iaa0ff526707be5b21bf746767f6241f4f0b6c39e

Conflicts:
	packages/SystemUI/src/com/android/systemui/recent/RecentsPanelView.java
Multi-user support for phones

Allow multi-user support on devices that previously didn't have it without
hard-coding it on.

ps2: Give it the nuclear touch.
ps3: Correct initialization.

Change-Id: I376f3f51ee1d8843d0977384101f93e23e278c97