Auto merge of #19279 - canaltinova:force-broken-image, r=emilio

style: Move -moz-force-broken-image-icon out of mako

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix part of #19015.

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- [X] These changes do not require tests because these are just refactoring.

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components/style/values/specified/mod.rs

@@ -55,6 +55,7 @@ pub use self::table::XSpan;
 pub use self::text::{InitialLetter, LetterSpacing, LineHeight, TextDecorationLine, TextOverflow, WordSpacing};
 pub use self::time::Time;
 pub use self::transform::{TimingFunction, Transform, TransformOrigin};
+pub use self::ui::MozForceBrokenImageIcon;
 pub use super::generics::grid::GridTemplateComponent as GenericGridTemplateComponent;
 
 #[cfg(feature = "gecko")]
@@ -84,6 +85,7 @@ pub mod table;
 pub mod text;
 pub mod time;
 pub mod transform;
+pub mod ui;
 
 /// Common handling for the specified value CSS url() values.
 pub mod url {