IVirtualCharsService is now a pure service (not ILanguageService) that is used in shared analyzer layer. A thin shim IVirtualCharsLanguageService has been added on top of IVirtualCharsService for clients that want MEF based discovery of this service. This follows the design used for syntax facts being split into pure service and a thin language service shim on top of it.

Add FirstAncestorOrSelf extension with an argument

Improve test performance

Port UseSimpleUsingStatement analyzer/fixer/test to shared layer

Port UseSystemHashCode analyzer/fixer/tests to shared layer

Port C# MisplacedUsingDirectives to shared layer

Port C# MakeStructFieldsWritable analyzer/fixer/tests to shared layer

Remove unnecessary rename parameters.

Remove duplicate target from Roslyn.Test.Utilities

Port MakeLocalFunctionStatic analyzer and tests to shared layer

Move away from IEnumerables in core rename results.

Respond to breaking package changes

Pool delegates for IsSupportedDiagnostic