[WIP]Multi Window

Trying to port - https://gerrit.omnirom.org/#/c/53

PS2: removed white spaces -.-
PS3: missing stray comma -.-

Change-Id: I2eac6d3d2bcca45dc0df465a40765b06b3f20f52

Conflicts:
	core/java/android/app/Activity.java
	core/java/android/app/IActivityManager.java
	packages/SystemUI/src/com/android/systemui/recent/RecentsPanelView.java