Support FoldingFeature for CONCURRENT state

Some emulated states such as CONCURRENT can be used in multiple
base/physical states (OPENED and HALF_OPENED).

This change adds support for the one-to-many mapping by:
  1) Adding COMMON_STATE_USE_BASE_STATE constant. An internal state
     where the CommonFoldingFeature.State should be derived from the
     base/physical device state.
  2) Updated DeviceStateCallback implementation which now listens to
     both onStateChanged (existing) and onBaseStateChanged (new).
     For emulated states configured as COMMON_STATE_USE_BASE_STATE,
     the base/physical state is sent to the client.

Slight code cleanup:
  1) Adds COMMON_STATE_NO_FOLDING_FEATURES which is used by some
     device configurations but not currently defined. This constant
     is used for device states where folding features do not exist.
  2) A few function/variable renames
  3) Added annotations

Bug: 268613897
Test: Using sample app, enter concurrent mode and then check
      folding features

Change-Id: I8e2ad9e52996d6e337b22a21312518bf839c5670