Some editors use diagnostics from SourceKit to replace build issues. This causes issues if the diagnostics from SourceKit are formatted differently than the build issues. Make sure they are rendered the same way, removing most uses of `DiagnosticsEditorMode`.
To do so, always emit the `add stubs for conformance` note (which previously was only emitted in editor mode) and remove all `; add <something>` suffixes from notes that state which requirements are missing.
rdar://129283608
Rather than relying on the NameAliasType we get by default for references
to non-generic typealiases, use BoundNameAliasType consistently to handle
references to typealiases that are formed by the type checker.
This fixes several issues:
- By default parent types of alias types are not printed which results in
- Erroneous fixits, for example when casting to 'Notification.Name' from a string, which ends up adding erroneous cast
as "Name(rawValue: ...)"
- Hard to understand types in code-completion results and diagnostics
- When printing with 'fully-qualified' option typealias types are printed erroneously like this "<PARENT>.Type.<TYPEALIAS>"
The change make typealias printing same as nominal types and addresses the above.
