Remove unnecessary code style diagnostic descriptors

* Add DisallowAddingImports option

* Disambiguate completion in integration test

Skip test CustomizableTagsForUnnecessaryCode

Merge release/dev16.8 to master

Terminate the integration test process if cleanup fails

Avoid heavy contention in OOP reading from temporary storage

* Better handling of OOM and exceptions in EnC analyzer

* Do not trigger fail fast on OOM exception unless the process actually runs out of memory

Fixes #35415

Check if $insertionDir exists before getting children.

Merge release/dev16.8 to master

Analyzer driver performance improvements

Move DateAndTime embedded language to the features layer

AreStringValuesEqual for real

Add a cache for AnalyzerConfigSets

Ensure the Compilation's options are changed on .editorconfig changes

Implement ability to extract code into a new base class if there is no other base class already. 

* Uses shared code with similar things like Extract Interface and Pull Members Up
* Shares UI with those two features as well 

Quick info for inline parameter name hints

Diagnostics for CommitOnSave failures

There's a combination of flags to build.ps1 that doesn't do the VSSetup related stuff, so the insertion dir doesn't exist. This is used in CI that indexes Roslyn source code. Otherwise it fails the build.

Use C# 'not' pattern when available.

We were correctly producing a new CompilationOptions but failed to
update an existing Compilation if one had been computed first.

Fixes https://github.com/dotnet/roslyn/issues/46784