This fixed DevDiv.1158790 — Spurious errors, warnings and messages in IDE from background analysis, which
basically results in a bunch of warnings in the IDE:

     The referenced component 'C:\Program Files (x86)\Reference Assemblies\Microsoft\Framework\.NETPortable\v4.5\Profile\Profile7\mscorlib.dll' could not be found.

C#/VB project system do not support conditional references and treat them as always being present. This <Reference was being included for all projects regardless
of the condition, confusing Visual Basic project system. Moved it to _ExplictReference concept which already exists for adding mscorlib (see <_ExplicitReference> in Microsoft.CSharp.CurrentVersionCommon.targets)

InternalsVisibleToTypeScript items are showing up the Solution Explorer visual tree
as missing items (because the C# project system treats them as files). Hide them
like the other InternalsVisibleToXX items.

Building BasicRoslyncDiagnosticAnalyzers.project resulted in a build
warning about not being able to find System.Data.

Portable projects themselves don't need to specify any references, as
they are implicitly added by the portable targets. Remove all framework
references, which also cleaned up the warning.

VS crash during EnC around active statements (#3894)

- apply feedback: code cleanup

Move file system completion support from Features layer to EditorFeatures layer

At the moment, these aren't used by any completion providers in the features layer. Until we decide that this is ready to support cross-platform, let's keep them in the editor features layer closer to the providers that actually use them.

Adjust API of ultimately instantiable classes to have protected ctors

Fix NREs in Interactive Command completion list

Remove workaround for a fixed bug in DiaSymReader

Fixes #4041

Add special case to object creation completion to not commit 'object' on '{'

Fixes #1428
Closes #2396

Add project.lock.json files for CoreCLR projects

- apply feedback: code cleanup

Ensure that the VerifyProviderCommit helper correctly inserts commit characters into the editor (or at least a reasonable approximation) to allow unit tests using this helper to better state their expectations.

Update DiaSymReader.Native to v1.1.0 that has GetSymReader export

Fix outlining banner with whitespace between hash and region.

VS crash during EnC around active statements

It updates earlier C# implementation and ports to VB (#3894)

Make PdbUtilities portable

Test Fixup for a Line Normalization Issue.

When completion preselects 'object', it becomes very cumbersome for a user to type 'new {' to create an anonymous object. Instead, they get 'new object {' inserted into the editor, which is never really desirable since System.Object doesn't have any properties. This tweak changes completion not to commit in the very specific case of typing '{' when the underlying preselected completion item is System.Object.

Fixes issue #4115.

It normalizes the line endings of the expected text in the CSharpEditorFeatures OrganizeImportsTests so that the test will compare to the correct expected value even if the input line endings are '\n' isntead of '\r\n'.

Test Fixup for a Line Normalization Issue.

This is a workaround for Issue #4109. It normalizes the line endings of the expected text so that the test will compare to the correct expected value even if the input line endings are '\n' isntead of '\r\n'.

Fixes #4105.

- apply feedback: unify C# and VB

Make InteractiveWindow states explicit