Add controller for Media operation

-Access LocalMediaManger to display avilable output devices information
-Access LocalMediaManger to do media operation, such as volume adjustment,
switching output device, grouping
-Access MediaController to show media content information
-Add MediaOutputControllerTest for unit test

Bug: 155822415
Test: atest MediaOutputControllerTest
Change-Id: I9eb6e3b0a6e584637aecb4132dbc2b138c6d1530