When swiping notifications it doesn't clip early anymore

Previously notifications started to clip before reaching
the edge. We're now changinging the flags to dismiss with
translation instead of clipping the contents.

This is change 1/2 as the notification container should
clip the notification now, which is especially noticeable
in split shade.

Bug: 181887261
Test: dismiss notifications, visually observe no clipping
Change-Id: I003b1486ce64dd127a90ca2d9f982230eba79f60