Auto merge of #17754 - SergeevPavel:system-colors-refactor, r=SimonSapin

replace vector iteration by ascii_case_insensitive_phf_map

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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 #15994 (github issue number if applicable).

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- [ ] These changes do not require tests because _____

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components/style/properties/longhand/color.mako.rs

@@ -121,21 +121,20 @@
 
         impl SystemColor {
             pub fn parse<'i, 't>(input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i>> {
-                #[cfg(feature = "gecko")]
-                use std::ascii::AsciiExt;
-                static PARSE_ARRAY: &'static [(&'static str, SystemColor); ${len(system_colors)}] = &[
-                    % for color in system_colors:
-                        ("${color}", LookAndFeel_ColorID::eColorID_${to_rust_ident(color)}),
-                    % endfor
-                ];
-
-                let ident = input.expect_ident()?;
-                for &(name, color) in PARSE_ARRAY.iter() {
-                    if name.eq_ignore_ascii_case(&ident) {
-                        return Ok(color)
+                ascii_case_insensitive_phf_map! {
+                    color_name -> SystemColor = {
+                        % for color in system_colors:
+                            "${color}" => LookAndFeel_ColorID::eColorID_${to_rust_ident(color)},
+                        % endfor
                     }
                 }
-                Err(SelectorParseError::UnexpectedIdent(ident).into())
+
+                let ident = input.expect_ident()?;
+                if let Some(color) = color_name(&ident) {
+                    Ok(*color)
+                } else {
+                    Err(SelectorParseError::UnexpectedIdent(ident).into())
+                }
             }
         }
     % endif