Fix SensorUseDialog UI issues

The SensorUseDialog (displayed when the camera or microphone is
accessed while the global camera/microphone toggle is disabled)
currently has a few issues:

1. Upon opening the dialog, a rounded rectangle with the text
   "System UI" momentarily flashes on the screen. This is
   undesirable/unexpected.
2. When the user rotates the device, the dialog exits. This is
   unexpected: the dialog should remain open while the device is
   rotated.

This change fixes both issues.

Fix: 294748342
Test: atest CameraMicIndicatorsPermissionTest
Change-Id: I212ba868e8b0221113b0a6ed13aa81466555708e