Revert "Enable insets flag for IME"

This reverts commit 1f0b2753.

Reason for revert: Crashes android.anim on a wembley
Bug: 149121559
Test: Local build of wembley with this reverted doesn't crash android.anim.

Change-Id: Ie2b9ce95114082d07fa6fddd1ec6d0cb345bd860