Fixes #2605 "Lightbulb suggests renaming a type to 'var'"

This change disables using Rename Tracking to rename to/from "var" and "dynamic" in C#.

Separate factory methods for each of the projects that consumes it and a
little less copying.

...the same way we expand display classes and state machines.  If we see a
local or parameter with a transparent identifier generated/mangled name,
we should instead include the properties of its (anonymous) type in our
list of bindable symbols.

Points of interest:
1. Transparent identifiers can be chained (i.e. have transparent
identifier properties).
2. Transparent identifiers can be captured (i.e. they might be display
class fields, rather than locals or parameters).
3. Display class instance locals cannot appear within transparent
identifiers (i.e. the recursion goes in only one direction).
4. For the benefit of the debugger, we're actually using fields, rather
than properties.  As a bonus, this was more consistent with the display
class case and, therefore, easier to implement.

TODO: Make a (hopefully) similar change in VB.

we forgot to add null check before calling GetProject

Fixes #2567

Fixes #2623

This change removes all C# specific references from
MS.CA.Workspaces.CSharp.Desktop.dll.  This demonstrates the pattern by
which we could migrate the language specific MSBuild code into a shared
DLL which has no language specific dependencies.  This pattern will
allow us to delete both MS.CA.W.CSHarpDesktop and
MS.Ca.W.VisualBasic.Desktop.

Fixes #2232

Prevent crash by avoiding QualifiedName->PredefinedTypeName simplification inside QualifiedNames.

The BitArray approach wasn't meaningfully reducing complexity, so we'll
revert to an earlier approach that reduces allocations (by reusing an
existing ReadOnlyCollection<byte> as the backing data when possible).

Fixes #2549

This reverts commit cdf6029c.

Fixes #2631

Centralized some of our scattered uses of reflection to PortableShim.
While moving I verified all of the APIs are a part of the CoreFX +
Portable plan.

Fixes part of internal TFS bug #1167415.

We have reports of the BufferUndoState being unavailable in
UndoTemporaryEdits when inline rename has been dismissed due to an
external workspace change. This change prevents the crash by checking
for the existence of the relevant BufferUndoState while we await more
information on what leads to this state.