* Add all nullable-related warnings to ErrorFacts

* Fix test failures and add a bit more coverage

* Emit tests

* Report rude edits for unsupported DIM operations

* Allow EnC tests to specify TFMs to build against

* EnC: test against netcoreapp30

* Test fixes

* Fix merge

Expand introduced using statement to include encompassed locals

Fixes #36241

Fixes #37187

Enable .editorconfig discovery by default

Implements https://github.com/dotnet/csharplang/issues/2389
Fixes #35958

Note that the switch expression conversion is not a standard implicit conversion.  Specifically, it should not be considered as a valid implicit conversion as input to a user-defined conversion, as that could permit two chained user-defined conversions.

Also changes binding of switch expression to ECMA so it can interact properly with switch expressions.
Fixes #14965

 Avoid boxing in string concatenation 

- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19364.1

Resolves #33344

Relates to #29821
Fixes #34409

Merge liveshare changes to do dual insertion.

* Update dependencies from https://github.com/dotnet/arcade build 20190711.7

- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19361.7

* Update dependencies from https://github.com/dotnet/arcade build 20190712.5

- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19362.5

* Update dependencies from https://github.com/dotnet/arcade build 20190713.1

- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19363.1

Show infobar for recommending installation of FxCopAnalyzers NuGet/VSIX

Address PR feedback and add an internal abstract property `SyntaxEditorBasedCodeFixProvider.CodeFixCategory` to determine the category of code fixes offered by our code fixers.

Completion timebox

Fixes #29819

Move refactorings to common helpers

Move 'Wrapping' code actions down to 'Feature' layer.

* Top-level types enumeration refactoring

* Simplify DefinitionMap

* Include namespaces in synthesized definition map

* Add SynthesizedNamespaceSymbol

* Embedded Attributes

* Test synthesized attributes

* Clean up EnC tests

* Clean up symbol matcher tests

* Ref readonly return type, in parameter symbol matching tests

* Enable using ref readonly returns, in parameters, ref structs during debugging

* More tests

* ReadOnly struct members

* Fix langauge version mismatch

* Merge fix ups

* Feedback, skip tests

Rename TypeArgumentsNullableAnnotations to TypeArgumentNullableAnnotations

* dotnet/master:
  Fix master build (#37163)
  Add error for multiple null suppressions (#37139)
  Check for uninitialized non-nullable field-like events (#37073)
  EnC emit tests for C# 8.0 patterns (#37025)
  Update dependencies from https://github.com/dotnet/arcade build 20190710.8
  Update dependencies from https://github.com/dotnet/arcade build 20190709.6
  [master] Update dependencies from dotnet/arcade (#37001)
  Add annotations to HostWorkspaceServices.cs and HostLanguageServices.cs
  Add nullable annotations to members in Solution.cs, SolutionInfo.cs, and SolutionState.cs
  Annotate Contract.cs
  Add nullable annotations and fixes to Workspace.cs
  Fix typo in documentation comment for Workspace.Dispose
  Check in copy of NullableAttributes.cs copied from coreclr
  Use switch expressions to simplify GetAccessibilityAndModifiers