We were only keeping track of `RawSyntax` node IDs to incrementally transfer a syntax tree via JSON. However, AFAICT the incremental JSON transfer option has been superceeded by `SyntaxParseActions`, which are more efficient.
So, let’s clean up and remove the `RawSyntax` node ID and JSON incremental transfer option.
In places that still need a notion of `RawSyntax` identity (like determining the reused syntax regions), use the `RawSyntax`’s pointer instead of the manually created ID.
In `incr_transfer_round_trip.py` always use the code path that uses the `SyntaxParseActions` and remove the transitional code that was still using the incremental JSON transfer but was never called.
If the position is in the region that is inserted by the edits,
'pre-edit' position shouldn't exist. So we cannot reuse the node at the
position.
rdar://problem/45259469
https://bugs.swift.org/browse/SR-8995
Also fix Edit::intersectsOrTouchesRange check only returning true when the
ranges overlapped, rather than when they overlapped or 'touched'.
Resolves rdar://problem/45108439
