Auto merge of #155671 - nnethercote:simplify-Config-track_state, r=bjorn3

Simplify `Config::track_state`.

This is a callback used to track otherwise untracked state. It was added in rust-lang/rust#116731 for Clippy. (It was originally named `hash_untracked_state`, and examples in the rustc-dev-guide still use that name.) The `StableHasher` argument is unused, and probably has never been used. There is a FIXME comment pointing this out, which was added more than a year ago.

This commit removes the `StableHasher` callback argument. This also removes the need for `Options::untracked_state_hash`.

r? @bjorn3

Author: bors

examples/rustc-interface-example.rs

@@ -50,7 +50,7 @@ fn main() {
         make_codegen_backend: None,
         expanded_args: Vec::new(),
         ice_file: None,
-        hash_untracked_state: None,
+        track_state: None,
         using_internal_features: &rustc_driver::USING_INTERNAL_FEATURES,
     };
     rustc_interface::run_compiler(config, |compiler| {
@@ -72,4 +72,4 @@ fn main() {
             }
         });
     });
-}
+}

examples/rustc-interface-getting-diagnostics.rs

@@ -78,7 +78,7 @@ fn main() {
         make_codegen_backend: None,
         expanded_args: Vec::new(),
         ice_file: None,
-        hash_untracked_state: None,
+        track_state: None,
         using_internal_features: &rustc_driver::USING_INTERNAL_FEATURES,
     };
     rustc_interface::run_compiler(config, |compiler| {
@@ -97,4 +97,4 @@ fn main() {
     buffer.lock().unwrap().iter().for_each(|diagnostic| {
         println!("{diagnostic:#?}");
     });
-}
+}