[tree] properly copy entry list, also queried indices

[ferdymercury]

This Pull request:

Changes or fixes:

Fixes #13338

fyi @romainbqt

Checklist:

• tested changes locally
• updated the docs (if necessary)

[github-actions]

Test Results

    19 files      19 suites   3d 8h 38m 15s ⏱️
 2 809 tests  2 809 ✅ 0 💤 0 ❌
51 875 runs  51 875 ✅ 0 💤 0 ❌

Results for commit 87d6950.

[pcanal]

Most other places, we seem to be using:

Suggested change

	elist->fLastIndexQueried = fLastIndexQueried;
	elist->fLastIndexReturned = fLastIndexReturned;
	elist->fLastIndexQueried = -1;
	elist->fLastIndexReturned = 0;

why is it different here? (especially since I am not sure whether LastIndex returns is likely to need to be expressed in local entry number)

[ferdymercury]

I am not sure. It just fixed the issue (empirically)

[pcanal]

I think we do need to understand in order to be able to add a comment with the explanation (so that future maintainer do not spend time 'pondering' the differences). In particular in this case, I don't know whether it is assigning (as opposed to not assignment) or assigning to this particular values that fixes the problem (In particular since the later may or may not work for case of larger chains).