Auto merge of #21487 - cdisselkoen:remove-comment, r=jdm

Remove outdated comment in stylist.rs

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This comment on `cascade_style_and_visited` is unclear because it refers to `is_link`, which is not a parameter of that function.  It used to refer to a flag in `CascadeFlags` back when there was a `cascade_flags: CascadeFlags` parameter; that parameter was removed in commit cd04664.  I don't believe it accurately reflects how the code works anymore, and is best just removed.

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- [ ] `./mach build -d` does not report any errors
- [ ] `./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 touch comments

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components/style/stylist.rs

@@ -824,9 +824,6 @@ impl Stylist {
     ///
     /// layout_parent_style is the style used for some property fixups.  It's
     /// the style of the nearest ancestor with a layout box.
-    ///
-    /// is_link should be true if we're computing style for a link; that affects
-    /// how :visited handling is done.
     pub fn cascade_style_and_visited<E>(
         &self,
         element: Option<E>,