Rollup merge of #103774 - compiler-errors:dyn-trait-in-type-name, r=eholk

Format `dyn Trait` better in `type_name` intrinsic

Noticed this in #103764 (though not related to that PR at all!)

```rust
trait Foo {
    type Bar;
}

fn main() {
    println!(
        "`dyn Fn(i32, i32) -> i32` => `{}`",
        std::any::type_name::<dyn Fn(i32, i32) -> i32>()
    );
    println!(
        "`dyn Foo<Bar = i32> + Send + Sync` => `{}`",
        std::any::type_name::<dyn Foo<Bar = i32> + Send + Sync>()
    );
}
```

```
`dyn Fn(i32, i32) -> i32` => `dyn core::ops::function::Fn<(i32, i32)>+Output = i32`
`dyn Foo<Bar = i32> + Send + Sync` => `dyn playground::Foo+Bar = i32+core::marker::Sync+core::marker::Send`
```

Just reuse `pretty_print_dyn_existential` which already makes an attempt to make its output stable.

1 files changed, 1 insertions, 4 deletions

diff --git a/src/test/ui/type/issue-94187-verbose-type-name.rs b/src/test/ui/type/issue-94187-verbose-type-name.rs
index 64f0c09e89b..3713a32eb11 100644
--- a/src/test/ui/type/issue-94187-verbose-type-name.rs
+++ b/src/test/ui/type/issue-94187-verbose-type-name.rs
@@ -12,8 +12,5 @@ fn main() {
     struct Wrapper<const VALUE: usize>;
     assert_eq!(type_name::<Wrapper<0>>(), "issue_94187_verbose_type_name::main::Wrapper<0>");
 
-    assert_eq!(
-        type_name::<dyn Fn(u32) -> u32>(),
-        "dyn core::ops::function::Fn<(u32,)>+Output = u32"
-    );
+    assert_eq!(type_name::<dyn Fn(u32) -> u32>(), "dyn core::ops::function::Fn(u32) -> u32");
 }