Move isMediaOutputDisabled() from Utils to LocalMediaManager

- Move isMediaOutputDisabled() from Utils to LocalMediaManager.
  The isMediaOutputDisabled() is used to check whether should
  disable the entry point of media output, it's not a general
  method for Settings. To reduce the usage of Utils.java,
  it's better to let LocalMediaManager handle this method.
- Add test cases.

Bug: 169378895
Test: make -j42 RunSettingsRoboTests
Change-Id: I5dbed2ad4de6dca8105414f8b7d7ce7141e258bd