Extract SimChangeListener to its own file

Test: as follows
    - built (bullhead)
    - flashed
    - booted
    - runtest frameworks-net passes
    - runtest -x full/path/to/SimChangeListenerTest.java passes
Bug: 32163131
Change-Id: If90539fe9a5dc07c7c24ed0b70b920d94065a623
3 files changed