Add missing include should prioritize the header with the class definition over headers with only a forward declaration (VS:1906590)

[bobbrow]

Set up a project thusly:

Header.h
class Foo; // just forward declaration

Header2.h
class Foo {}; // the definition

Source.cpp
Foo foo;

Actual:
In the current product, Foo in cpp file should squiggle with "undefined" error and hovering over it offers both headers as suggestions.

Expected:
The suggested includes should be only Header2.h (to bring the full definition)

This should be addressed in VS and VS Code