Auto merge of #23499 - est31:unused_code_removal_3, r=jdm

Remove unused code (3/N)

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Third PR in a series of PRs to remove unused/dead code from servo, powered by an (upcoming) tool of mine. Please take a look and tell me if you want to keep something.

* First PR: #23477
* Second PR: #23498

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `___` with appropriate data: -->
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #___ (GitHub issue number if applicable)

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because they only remove dead code

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components/style/properties/cascade.rs

@@ -421,7 +421,7 @@ impl<'a, 'b: 'a> Cascade<'a, 'b> {
     }
 
     #[inline(always)]
-    fn apply_declaration<Phase: CascadePhase>(
+    fn apply_declaration(
         &mut self,
         longhand_id: LonghandId,
         declaration: &PropertyDeclaration,
@@ -544,7 +544,7 @@ impl<'a, 'b: 'a> Cascade<'a, 'b> {
             // FIXME(emilio): We should avoid generating code for logical
             // longhands and just use the physical ones, then rename
             // physical_longhand_id to just longhand_id.
-            self.apply_declaration::<Phase>(longhand_id, &*declaration);
+            self.apply_declaration(longhand_id, &*declaration);
         }
 
         if Phase::is_early() {