Scribe in IMF: Introduce filters in CursoAnchorInfo API 7/N

New filter modes for InputConnection#requestCursorUpdates(mode) to allow
partial data in cursor/anchor updates.
Selective data helps with speedy CursorAnchorInfo updates.

Test: atest InputMethodServiceTest
Bug: 203086136

Change-Id: Ibba06e9a2533ca91c5cc215dfb18d21c9a74fb73