Add a regression test for rust-lang#89935

Author: JohnTitor

src/test/ui/typeck/issue-89935.rs

@@ -0,0 +1,18 @@
+// check-pass
+
+trait Foo: Baz {}
+trait Bar {}
+trait Baz: Bar {
+    fn bar(&self);
+}
+
+impl<T: Foo> Bar for T {}
+impl<T: Foo> Baz for T {
+    fn bar(&self) {}
+}
+
+fn accept_foo(x: Box<dyn Foo>) {
+    x.bar();
+}
+
+fn main() {}