[markers] fix false positive problem tabbar decorators

[vince-fugnitto]

What it does

Fixes #6109

• fixes an issue where problem tabbar decorators wrongly display false positives
• with the change, only error and warning decorators are displayed in the tabbar which
  is consistent with the problem decorators present in the explorer
• with the change, only one decorator (max severity) is ever decorated (no need for unnecessary rendering)

How to test

1. open the application with a workspace present
2. open an arbitrary file and produce errors and warnings
3. the highest severity should be displayed in the tabbar as a decoration (error and warning only)
4. the decoration should match that of the explorer

Review checklist

• as an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• as a reviewer, I agree to behave in accordance with the review guidelines

Signed-off-by: Vincent Fugnitto vincent.fugnitto@ericsson.com

[akosyakov]

@lmcbout could you please finish the review by testing, code-wise it looks to me, thank you!

[lmcbout]

@akosyakov looking at it right now.

[lmcbout]

I notice something, but code wise and performance, this PR is a good improvement.

Steps:

1. have the problems-view open at all times
2. open 2 files with hints / warnings -
   quick-open-task.ts (4), and task-problem-pattern-registry (1)
3. add an error in quick-open-task.ts (ex: const jj=9)
4. it shows the error in the file quick-open-task.ts 👍
5. if you run in debug mode with a stop in problem-tabbar-decorator.ts ~ line 64, you notice that both open files are decorated each time there is a modification, not only the modified file. I think for an improvement, if we just look for the modified file to set the decorator, it would improve the performance.

[vince-fugnitto]

@lmcbout does the PR work correctly and fix the bug? I'm not attempting to address the performance as part of the PR but rather I attempted to fix the bug and be as optimized as I can be.

I believe in general the performance should be handled by #6146

[lmcbout]

Works nicely
Performance in other issue is fine

[vince-fugnitto]

Works nicely
Performance in other issue is fine

Thank you for the review! 👍