Fixes #43788
TodoCommentOptions and TodoCommentOptionsProvider were defined in EditorFeatures layer and we only serialize the options defined in Workspaces and Features layer to the OOP side: https://github.com/dotnet/roslyn/blob/287a25a51324f252e61b6f2186e7df60c8a6161b/src/Workspaces/Core/Portable/Options/GlobalOptionService.cs#L79-L85

In future, we either need to add support to serialize all changed options to OOP (could be expensive) or somehow enforce that all the OOP related options are defined in Workspaces and Features layer.

Co-authored-by: NJason Malinowski <jason@jason-m.com>

Adds a new "record" declaration kind and enables when parsing as C#
preview. If C# preview is not enabled, parsing is unchanged.

This moves the fetching of the nullable state into the first part of
quick info, which is figuring out the data/model. The function to take
that model and convert it to the display information can now go static
since it's not relying on other indirection.

The Quick Info service mostly defers to the symbol description service
to do most of it's work; the symbol description service takes a symbol
and a SemanticModel + position to build up the description of the
symbol, using that position for minimally qualifying types in some
cases. This position was also being used by the symbol description
service to see if the original invocation point was an await, and if so
it switched to special behavior to give a different message entirely;
there was some logic in Quick Info itself to also accomodate that.

This moves that special handling back up to Quick Info, and also does
a bit of a refactoring to include all of the decisions for what Quick
Info will show into a struct. This will be used later to help the LSIF
tool because it means if the two structs are equal than we know the
two Quick Info contents would the same and we can reuse it.

I am just a simple developer trying to send these cancellation tokens downstream where they belong

* Revert "Revert "Refactoring of Active Statement tracking for OOP""

* Only apply active statement tracking for C# and VB buffers

ConvertTupleToStruct invokes our existing services for generating
GetHashCode methods; that service checks whether System.HashCode is
available, and if so uses it rather than implementing the hash code
combining manually. The code to generate GetHashCode correctly not just
grabs the type but also tries to check whether type is accessible to
the struct being generated. It's possible for System.HashCode to be
internal if some library you're referencing has embedded it's own copy;
in this case we were trying to check if the System.HashCode was
accessible to the code generation symbol; if the System.HashCode was
internal it then checks the assembly symbols for InternalsVisibleTo,
but since the code generation symbol never had a ContainingAssembly this
would crash with a null reference.

Much of this code is null annotated, but unfortunately we have yet to
annotate ContainingAssembly, so the line of code that let a null get
into the system was here:

https://github.com/dotnet/roslyn/blob/884fdff6f8a87faa7f6e65d762bd6d7b2025da74/src/Workspaces/SharedUtilitiesAndExtensions/Compiler/Core/Extensions/ISymbolExtensions_Accessibility.cs#L230

My fix is to create the code generation INamedTypeSymbol with a
containing assembly, which allows the rest of the checks to work
correctly.

Fixes #44603