Rollup merge of #144694 - compiler-errors:with-self-ty, r=SparrowLii

Distinguish prepending and replacing self ty in predicates

There are two kinds of functions called `with_self_ty`:
1. Prepends the `Self` type onto an `ExistentialPredicate` which lacks it in its internal representation.
2. Replaces the `Self` type of an existing predicate, either for diagnostics purposes or in the new trait solver when normalizing that self type.

This PR distinguishes these two because I often want to only grep for one of them. Namely, let's call it `with_replaced_self_ty` when all we're doing is replacing the self type.

clippy_lints/src/needless_borrows_for_generic_args.rs

@@ -417,7 +417,7 @@ fn replace_types<'tcx>(
                 {
                     let projection = projection_predicate
                         .projection_term
-                        .with_self_ty(cx.tcx, new_ty)
+                        .with_replaced_self_ty(cx.tcx, new_ty)
                         .expect_ty(cx.tcx)
                         .to_ty(cx.tcx);