Auto merge of #86143 - bjorn3:revert_revert_merge_crate_disambiguator, r=michaelwoerister

Reland "Merge CrateDisambiguator into StableCrateId"

Reverts https://github.com/rust-lang/rust/pull/85891 as this revert of #85804 made perf even worse.

r? `@Mark-Simulacrum`

compiler/rustc_hir/src/definitions.rs

@@ -12,7 +12,6 @@ use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::stable_hasher::StableHasher;
 use rustc_data_structures::unhash::UnhashMap;
 use rustc_index::vec::IndexVec;
-use rustc_span::crate_disambiguator::CrateDisambiguator;
 use rustc_span::hygiene::ExpnId;
 use rustc_span::symbol::{kw, sym, Symbol};
 
@@ -325,7 +324,7 @@ impl Definitions {
     }
 
     /// Adds a root definition (no parent) and a few other reserved definitions.
-    pub fn new(crate_name: &str, crate_disambiguator: CrateDisambiguator) -> Definitions {
+    pub fn new(stable_crate_id: StableCrateId) -> Definitions {
         let key = DefKey {
             parent: None,
             disambiguated_data: DisambiguatedDefPathData {
@@ -334,7 +333,6 @@ impl Definitions {
             },
         };
 
-        let stable_crate_id = StableCrateId::new(crate_name, crate_disambiguator);
         let parent_hash = DefPathHash::new(stable_crate_id, 0);
         let def_path_hash = key.compute_stable_hash(parent_hash);