Fadeout based on roslyn tag 'unnecessary'.

[savpek]

Based on original PR #2646 from @akshita31

Requires OmniSharp/omnisharp-roslyn#1410 and OmniSharp/omnisharp-roslyn#1076 to be fully functional.

Without backend support (previous PR:s), this has few hard coding to fade most common situations without full blown analysis: (decided not to hard code anything at this point, requires analyzers.)

With backend support (theres Roslynator package that fadeouts some additional items from image):

Theres some mapping when fadeout occurs because VSCode doesn't support 'hidden' with fadeout, so those items must be converted to hints or fadeout doesn't work on them.

[codecov]

Codecov Report

Merging #2873 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2873   +/-   ##
=======================================
  Coverage   89.74%   89.74%           
=======================================
  Files          59       59           
  Lines        1570     1570           
  Branches       89       89           
=======================================
  Hits         1409     1409           
  Misses        149      149           
  Partials       12       12

Flag	Coverage Δ
#integration	100% <ø> (ø)	⬆️
#unit	89.74% <ø> (ø)	⬆️

Impacted Files	Coverage Δ
src/omnisharp/protocol.ts	83.03% <ø> (ø)	⬆️

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[codecov]

Codecov Report

Merging #2873 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2873   +/-   ##
=======================================
  Coverage   89.79%   89.79%           
=======================================
  Files          59       59           
  Lines        1588     1588           
  Branches       89       89           
=======================================
  Hits         1426     1426           
  Misses        151      151           
  Partials       11       11

Flag	Coverage Δ
#integration	?
#unit	89.79% <ø> (ø)	⬆️

Impacted Files	Coverage Δ
src/omnisharp/protocol.ts	83.03% <ø> (ø)	⬆️

---

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Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[savpek]

This is ready for review @rchande @akshita31

Requires latest version of omnisharp-roslyn master branch and analyzers enabled.

[filipw]

I would recommend to wait with this until there is official omnisharp-roslyn with the analyzers feature + that version is consumed by the C# extension.
Otherwise there is a setting that only works for "omnisharp.path": "latest" which is a bit confusing.

[akshita31]

@savpek Is it possible to add a test for this ?

[savpek]

Could @rchande @akshita31 check this out? It should be good to go and i use this at daily basis (custom build).

I'd like to use this PR test infra with #3089 since i ended up refactor diagnostic provider there a bit and it's good point to add more tests for diagnostics 🙂

[akshita31]

Looks good to me. Thanks @savpek

[akshita31]

@savpek Would you like to do another PR to add the changelog.

[savpek]

@akshita31 changelog #3105