Endpoint for use with GoToTypeDefinition VS Code command

[jtschuster]

VS Code has a command editor.action.goToTypeDefinition that is implemented for a number of languages, but not for C#. At the moment I don't see a way to use the existing endpoints to create this functionality. A new endpoint to go to the definition of the type / class of a variable would be helpful in C# workflow, especially when using implicitly typed variables that don't have the name of the type anywhere in the file.

Example:
file1.cs:

class C {
    C NamedConstructor() { return new C(); }
}

file2.cs:

class D {
    void method() 
    {
        var variableName = NamedConstructor();
    }
}

GoToTypeDefinition at the position of variableName would return the definition of the class C in file1.cs.