Update OutputSwitcher from MediaOutputSlice to MediaOutputDialog in Settings

-Update entry point at media indicator in volume panel
-Update entry point at remote media slice in volume panel
-Update entry point at remote volume group in Sound Settings
-Update entry point at media output preference in Sound Settings
-Hide Media output dialog when the caller is not active

Bug: 155822415
Test: make -j50 RunSettingsRoboTests
Change-Id: Ib6c86067522925c439f336644e4d027dbae3379c