Preserve status of tests when re-discovering automatically

[DonJayamanne]

For #4576

• Pull request represents a single change (i.e. not fixing disparate/unrelated things in a single PR)
• Title summarizes what is changing
• Has a news entry file (remember to thank yourself!)
• [n/a] Has sufficient logging.
• [n/a] Has telemetry for enhancements.
• Unit tests & system/integration tests are added/updated
• [n/a] Test plan is updated as appropriate
• [n/a] package-lock.json has been regenerated by running npm install (if dependencies have changed)
• [n/a] The wiki is updated with any design decisions/details.

[codecov]

Codecov Report

Merging #4638 into master will decrease coverage by 1%.
The diff coverage is 89%.

@@           Coverage Diff           @@
##           master   #4638    +/-   ##
=======================================
- Coverage      77%     77%   -<1%     
=======================================
  Files         445     446     +1     
  Lines       21071   21260   +189     
  Branches     3422    3478    +56     
=======================================
+ Hits        16219   16294    +75     
- Misses       4846    4962   +116     
+ Partials        6       4     -2

Flag	Coverage Δ
#Linux	66% <88%> (+1%)	⬆️
#Windows	66% <88%> (+1%)	⬆️
#macOS	66% <88%> (+1%)	⬆️

[ericsnowcurrently]

The general approach seems right, e.g. the merge functions. However, as I've noted below, I'm not convinced that things are happening in the right place.

[ericsnowcurrently]

Thanks for the updates. LGTM.