Make AbstractType less public

Summary: It is not needed in public API, but because some `Canonical = ...` point to it, Rust requires it to be public.

Reviewed By: JakobDegen

Differential Revision: D63791951

fbshipit-source-id: 713e75fe49401409c9086f3fd9a691e43b98d7a9

Author: stepancheg

starlark/src/values/types/starlark_value_as_type.rs

@@ -38,6 +38,7 @@ use crate::values::layout::avalue::AValueImpl;
 use crate::values::layout::heap::repr::AValueRepr;
 use crate::values::type_repr::StarlarkTypeRepr;
 use crate::values::typing::ty::AbstractType;
+use crate::values::typing::TypeType;
 use crate::values::AllocFrozenValue;
 use crate::values::AllocValue;
 use crate::values::FrozenHeap;
@@ -153,10 +154,10 @@ impl<T: StarlarkTypeRepr> StarlarkValueAsType<T> {
 }
 
 impl<T: StarlarkTypeRepr> StarlarkTypeRepr for StarlarkValueAsType<T> {
-    type Canonical = <AbstractType as StarlarkTypeRepr>::Canonical;
+    type Canonical = <TypeType as StarlarkTypeRepr>::Canonical;
 
     fn starlark_type_repr() -> Ty {
-        AbstractType::starlark_type_repr()
+        <Self::Canonical as StarlarkTypeRepr>::starlark_type_repr()
     }
 }
 

starlark/src/values/typing/ty.rs

@@ -26,6 +26,7 @@ use crate::typing::TyBasic;
 use crate::values::StarlarkValue;
 
 /// Type of type.
+#[doc(hidden)]
 #[derive(
     Debug,
     derive_more::Display,