Fix completion crash in tuple in alias

Stop swallowing JTF exceptions

Merge dev15.4.x to master

Fix issue with merging parameters

We were not generating a cached completion item rule for a non-preselected item in a tuple context that was also an alias context
Fixes https://github.com/dotnet/roslyn/issues/22002

The testing instructure for CoreCLR currently runs all assemblies in
parallel in a single process, so resources, which are static and lazy
initialized, must have thread synchronization. Otherwise, tests which
depend on object or symbol identity could fail if they retrieve
different copies of the same resource.

Fixes #21937

21898 - Fixed typo in help message

Avoid AggregateException in TaskExtensions.WaitAndGetResult

fixing merge break: adding document attribute to pdb in broken tests

InternalsVisibleToCompletionProvider

- Fixed variable typo in all files I could find it in

added more diagnostic info on OOP code.

* Use DSRN version 1.7.0-beta-25631

* Fill in missing document entries in PDB tests

* Update pdb to xml converter to 1.1.0-beta1-62106-02

* Full Windows PDB determinism

* Update DSRN to 1.7.0-private-25621

* Avoid caching zero chunks

* PR feedback

Merge dev15.4.x to master

* Load DSRN from alternate path if set

* Fix error reporting

Add support for the CLI invoking Roslyn without CscToolPath

Don't write files in CompilerPackage if not needed

Merge pull request #20805 from dotnet/features/non-trailing

Disabling flakey VisualBasic.BasicEditAndContinue.MultiProjectDebuggingWhereNotAllModulesAreLoaded (#21926)

* disabling flakey test

* disabling all VB ENC tests

CompilerPackage was previously being lazy and would just delete and
rewrite files as needed when the package was loaded, even if the
machine would ultimately be left in the same state at the end.
For the old project system (which didn't monitor such file changes)
this wasn't bad, but with the new project system it now reloads projects
in response to changes which can be quite expensive.

Fixes dotnet/roslyn#21838.