[SB][Screen Chips] Show a stop dialog for screen share and screen cast.

Bug:  332662551
Flag: com.android.systemui.status_bar_screen_sharing_chips
Test: Start sharing your screen to another app on your phone -> click on
chip -> verify dialog is shown. Click "Stop sharing" -> verify screen
sharing stops
Test: Start casting your screen to a different device -> click on chip
-> verify dialog is shown. Click "Stop casting" -> verify screen casting
stops
Test: atest statusbar.chips package & mediaprojection package

Change-Id: I9d8c2997c9962c05e6d903c226ede5d57670a495