Make any TyName intersect with any TyCustom

Summary:
Following diff D48893103 implements `Provider` type as `TyUser` (which is `TyCustom`), but does not yet convert concrete provider types to `TyUser`. So we need to intersect `TyUser` with `TyName`.

This makes typechecker a bit weaker than before, but that's fine because the plan is to get rid of `TyName`.

Reviewed By: ianlevesque

Differential Revision: D48893554

fbshipit-source-id: 976dd58685cf7f11e648b812d73cf07631920ae9

Author: stepancheg

starlark/src/typing/oracle/ctx.rs

@@ -854,6 +854,7 @@ impl<'a> TypingOracleCtx<'a> {
         match (x, y) {
             (TyBasic::Any, _) => true,
             (TyBasic::Name(x), TyBasic::Name(y)) => self.intersects_name(x, y),
+            (TyBasic::Name(_), TyBasic::Custom(_)) => true,
             (TyBasic::Name(x), y) => Some(x.as_str()) == y.as_name(),
             (TyBasic::List(x), TyBasic::List(y)) => self.intersects(x, y),
             (TyBasic::Dict(x_k, x_v), TyBasic::Dict(y_k, y_v)) => {