Now Evidence isn't unique for each Chunk: Occurrence Chunks fully
share evidence and justifications with their activating match.
So, less collections of justifications are created, approx. 2 times less.
Relates to machinery introduced in MPSCR-47.
Previously parent match was maintained in Controller on Java call stack.
Now this stack of parent matches is maintained manually in MatchJournal.
So MatchJournal gains new invariant: parentChunk()
returns correct parent after each logMatch() call.
Several tests fail, also need to maintain this
invariant after logActivation() calls.
Make Occurrence a Justified entity and drop .justifications() from
ConstraintOccurrence.java because justifications are used only internally.
A single justification is now called Evidence (typealias to Int),
so Justified entities are justified by Evidence-s.
StateFrameStack adds no functionality but requires too much processing.
Rename StateFrameStack -> LogicalState.
Rename ProcessingStateImpl -> ConstraintsProcessing.
Simplify occurrence's logical observer.
Introduce transient dependency on controller to LogicalState.
Keep logical state as part of session token, avoid re-initializing
all logical observers.
Make replaying of match journal independent of controller.
It caused a situation when on the very next incremental evaluation session
occurrences carried a stale Controller along with all the state from previous session.
As a result, incorrect logic of program evaluation.
Small changes: rename MatchHistory -> StateAwareJournal; use referential
eq when iterating through chunks; provide only Pos, not Chunk from
current()/currentPos(); fix tests according to all this.
Grigorii Kirgizov