Revert "Revert "Migrate ENABLE_GRID_ONLY_OVERVIEW to aconfig flag""

This reverts commit 7b5472f9864f6d563284d5ea896d5b3aaa01747e.

Reason for revert: aconfig/SetFlagsRule actually works with TAPL tests (http://ag/c/platform/packages/apps/Launcher3/+/24991890/comment/8303a3c6_030ae00b/)
Bug: 270397206

Change-Id: I7529a64c3197e4c2b4d5fb1e46fb29bdea1e52e9
12 files changed