Remove unused class when the flag is enabled.

With the WB_MEDIA_MIGRATION flag enabled this class has no references as
we don't need a wrapper when using Surface.

More information at go/warren-buffers.

Bug: 393639229
Test: Build and run - no references with the flag enabled
Flag: com.android.graphics.libgui.flags.wb_media_migration
Change-Id: I11d1d86008d1f4eb20625d37573e9e538e9c8695