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TS has moved to newly added APIs, so remove the old APIs.
Fixes #11501

This reverts commit 1b6a83f9.

Fixes https://github.com/dotnet/roslyn/issues/11464

Add a public "MatchPriority" class that defines 2 possible values.

It's contained in the diagnostics window VSIX, which we include in
the full deployment.

* initial port from CSharpEssentials

* responding to feedback.
removing syntax rewriter and incorporating formatting rules into formatter

* responding to cryus' feedback

- general logic cleanup
- moving methods to abstract base class

* initial port from CSharpEssentials

* responding to feedback.
removing syntax rewriter and incorporating formatting rules into formatter

* responding to cryus' feedback

- general logic cleanup
- moving methods to abstract base class

it looks like diagnostic telemetry got broken when we introduced a new flag for diagnostic engines in update 1.

also recent engine v2 changes didn't report all telemetry data

More cleanup to do between RoslynCompletionSet and
FilteredRoslynCompletionSet.

Extending the supported functionality of the VisualStudio IntegrationTest Utilities and adding the start of 'CSharpAutomaticBraceCompletion'

Diagnostic/quick fix for adding braces to if's, else's, for's, foreach's, while's, do-while's, and using's.