Removed disabled overview actions at end of scroll

Updated visibility of the overview action bar so that when viewing
the clear all button at the end of the tasks it becomes hidden.
Previously, the overview actions were disabled so they were not
usable anyways. Updated the corresponding tests because expected
behavior was changed.

Test: Manual
Fix: 230508197
Change-Id: I64c91c682009808690d696032ffadefc86dfbac9