Auto-remove tracks with non valid config references in view->afterAttach

[cmdcolin]

Ref
#560

Procedure to test

Open a couple tracks
Delete one of those tracks from the config.json
Refresh the page

Expect: The track that was deleted will not be present on the refreshed page

Note that "all views would need to implement this functionality" as implemented here

[codecov]

Codecov Report

Merging #1275 into master will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1275      +/-   ##
==========================================
+ Coverage   58.84%   58.86%   +0.01%     
==========================================
  Files         415      415              
  Lines       18065    18071       +6     
  Branches     4213     4213              
==========================================
+ Hits        10630    10637       +7     
+ Misses       7163     7162       -1     
  Partials      272      272              

Impacted Files	Coverage Δ
...s/linear-genome-view/src/LinearGenomeView/index.ts	76.89% <100.00%> (+0.26%)	⬆️
packages/core/util/index.ts	81.50% <0.00%> (ø)
packages/core/rpc/coreRpcMethods.ts	86.88% <0.00%> (+1.63%)	⬆️

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[rbuels]

any way we can avoid all views having to do this?

maybe walk the state tree and validate all the references someplace central?

[cmdcolin]

Not sure. I tried doing a walk in session->afterAttach but only the session itself was returned....the timing is important for this because it has to remove the bad tracks before they get rendered...otherwise have to do crazy stuff to make everything involved in rendering a track robust to getConf throwing exceptions

[cmdcolin]

close by #1353