Remove UiEventLogger from NSSL

Move the UiEventLogger from NotificactionStackScrollLayout to the
NotificactionStackScrollLayoutController. The controller now adds
a listener to the NSSL so it knows when to alert.

Bug: 147245740
Test: atest SystemUITests && manual
Change-Id: Ia2cc3110d2b4f943f69f07573f9ff9fcd21c2c30
4 files changed