SysUI: Fix notification leak

Fix bug where we kept a reference to the old Notification when
we re-use notification entries on updates.

Bug: 16513124
Change-Id: I066ff7447952516e27e122df57d4e6e67ee1cea3
Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/BaseStatusBar.java
2 files changed