Ability to filter the Problems view by owner

[toptensoftware]

Currently all reported problems are shown in the problem panel regardless of who's reporting them - and there's no way to separate them out or distinguish them. This is particularly problematic for the Omnisharp C# extension where you'll often get duplicate errors - one from the compile/build and one from the code analysis.

See the screenshots in this issue showing how this broken out of the box. In fact, as evident by the confusion in that discussion it's not even obvious that these errors are being reported from two different sources. The fault has been closed even though it still occurs.

When the errors are copied from the problems panel and pasted into a text editor (see json below) it becomes obvious that one is reported by "csharp" and one is reported by "msCompile". It's the same error shown twice.

{
	"resource": "/c:/Users/Brad/Projects/testerrs/Program.cs",
	"owner": "csharp",
	"code": "CS1002",
	"severity": 8,
	"message": "; expected [testerrs]",
	"source": "csharp",
	"startLineNumber": 9,
	"startColumn": 46,
	"endLineNumber": 9,
	"endColumn": 46
}

{
	"resource": "/c:/Users/Brad/Projects/testerrs/Program.cs",
	"owner": "msCompile",
	"code": "CS1002",
	"severity": 8,
	"message": "; expected [C:\\Users\\Brad\\Projects\\testerrs\\testerrs.csproj]",
	"startLineNumber": 9,
	"startColumn": 46,
	"endLineNumber": 9,
	"endColumn": 46
}

Sometimes you'll want to move through a list of build errors, other times the list of problems detected roslyn/csharp extension is more useful. So, a couple of suggestions:

1. The ability to filter the problems view by the reporting owner. That would allow just showing build errors or just showing the analysis errors.
2. Show the owner of each problem in the problems view so it's more obvious who is reporting the problem (that would've prevented 90% of the discussion on the above linked issue with Omnisharp).
3. If neither of the above, at the very least the ability to "move to next/previous error" in the build output so that when there are duplicates there's at least one place where you can step through the list of problems as reported by the compiler without all the interference.

When there's one or two problems all this isn't too much of an issue, but during large refactorings the problems window can get clogged with hundreds of issues and the duplicates make it unusable - I just want a way to step through the actual current build errors.

[gjsjohnmurray]

/duplicate of #51103