Bug 1910646 - Do not assert that variables are computed before substituting references. r=firefox-style-system-reviewers,emilio

If the value of a custom property is a CSS-wide keyword in fallback, it
will not already be computed.

Differential Revision: https://phabricator.services.mozilla.com/D241773

servo/components/style/custom_properties.rs

@@ -2057,8 +2057,6 @@ fn substitute_one_reference<'a>(
     if reference.is_var {
         let registration = stylist.get_custom_property_registration(&reference.name);
         if let Some(v) = custom_properties.get(registration, &reference.name) {
-            #[cfg(debug_assertions)]
-            debug_assert!(v.is_parsed(registration), "Should be already computed");
             // Skip references that are inside the outer variable (in fallback for example).
             while references
                 .next_if(|next_ref| next_ref.end <= reference.end)

servo/components/style/properties_and_values/value.rs

@@ -343,12 +343,6 @@ impl ComputedValue {
         }
     }
 
-    /// Returns whether the the property is computed.
-    #[cfg(debug_assertions)]
-    pub fn is_parsed(&self, registration: &PropertyRegistrationData) -> bool {
-        registration.syntax.is_universal() || !matches!(self.v, ValueInner::Universal(_))
-    }
-
     /// Convert to an untyped variable value.
     pub fn to_variable_value(&self) -> ComputedPropertyValue {
         if let ValueInner::Universal(ref value) = self.v {

testing/web-platform/meta/css/css-variables/variable-css-wide-keywords.html.ini

@@ -1,6 +1,4 @@
 [variable-css-wide-keywords.html]
-  expected:
-    if debug: CRASH
   [`revert-layer` as a `var()` fallback for an unregistered custom property]
     expected: FAIL