Blur NSSL view when opening the primary bouncer from the shade

Rest of the shade is blurred from NPVC but that doesn't seem to affect NSSL

Test: Unit tests added
Flag: com.android.systemui.bouncer_ui_revamp
Fixes: 385364857
Test: verified manually,
 1. Open shade
 2. Tap on notification to open alternate bouncer
 3. Swipe up to go to primary bouncer
 4. Notifications should be visible and blurred
Change-Id: I91638147cc0e8d4aa5f26feb4c4d1ab13ea996c1