.. an abstract class. Then, MoveType, RenameFile, RenameType edits are
performed by different subclasses of the editor.

.. naming convention and remove unused ones.

For e.g. double clicking on a class should also show the codeaction.

Cut the following features:
1. Move type dialog
2. Make type partial.

Trimming the feature set being offered, targeting core scenarios and
dropping fringe features.

and export it for both C# and VB. Remove language specific subclasses
that weren't needed.
Also update tests to correctly instantiate the CodeRefactoringProvider
after the change.

for VisualBasic.

1. organize code
2. remove/reorder signatures
3. reduce fields
4. use expression lambda notation.
5. simplify code

around CodeAction and Editor types.

Reduce the no. of fields stored in State.

with nested private type

Most of the logic here is language agnostic, however there are some
differences between the syntax tree structure of C# and VB. Accounting
for these syntactic differences gets VB support working. Move to
new file, Move via UI dialog, Make type partial, all seems to work.