Remove the broadcast to createSystemUIUnderlay.

As planned, this should be migrated to an AIDL. Currently this broadcast causes a deadlock in trunkfood, so let's just remove it and land the AIDL very soon.

Bug: 411566363
Bug: 410392136
Bug: 403422950
Change-Id: I6f01b46498898b6ae4408a008ab01f15109e1483
Flag: android.view.contentcapture.flags.enable_system_ui_underlay
Test: atest CtsContentCaptureServiceTestCase