[flexiglass] Remove new media pipeline flag

This CL merges new media pipeline code into flexiglass.

Flag: com.android.systemui.scene_container
Bug: 326408371
Test: atest MediaViewControllerTest
Test: atest MediaDataProcessorTest
Change-Id: I0a264e52b4f3d64395dcdb43ccf093a53050ea3a
9 files changed