`RecursiveIterator.stream()` emits `StreamException` for notes in inner streams

[jacobtylerwalls]

const n = new music21.note.Note("C#");
const m = new music21.stream.Measure();
m.append(n)
const p = new music21.stream.Part();
p.append(m);
const s = p.recurse().stream();

StreamException: An entry for this object is not stored in this Stream.

[mscuthbert]

I've totally forgotten how this works on m21p let alone here. Does it use .template?

[jacobtylerwalls]

No, it just does getOffsetInHierarchy and then a bunch of coreAppend.

I think this is the missing piece:

music21j/src/music21/stream/iterator.ts

Lines 167 to 170 in 0d7aa31

	const o = ss.elementOffset(e, stringReturns);
	// try: getOffsetInHierarchy...
	// string returns;
	found.insert(o, <base.Music21Object><any> e);