Add a aconfig flag of disabling windowOptOutEdgeToEdgeEnforcement

The flag controls if windowOptOutEdgeToEdgeEnforcement is disabled or
not.

Bug: 377864165
Flag: com.android.window.flags.disable_opt_out_edge_to_edge
Test: presubmit
Change-Id: I85477f0300724dae9a5597437c96eacdad8b9d71