Auto merge of #29816 - Loirooriol:sync, r=mrobinson

Backport several style changes from Gecko (3)

<!-- Please describe your changes on the following line: -->
This continues https://github.com/servo/servo/pull/29772.

---
<!-- 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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- [X] There are tests for these changes OR
- [ ] These changes do not require tests because ___

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components/style/properties/longhands/box.mako.rs

@@ -320,6 +320,22 @@ ${helpers.predefined_type(
     rule_types_allowed=DEFAULT_RULES_EXCEPT_KEYFRAME,
 )}
 
+${helpers.predefined_type(
+    "animation-timeline",
+    "AnimationTimeline",
+    "computed::AnimationTimeline::auto()",
+    engines="gecko servo-2013 servo-2020",
+    servo_2013_pref="layout.2013.unimplemented",
+    servo_2020_pref="layout.2020.unimplemented",
+    initial_specified_value="specified::AnimationTimeline::auto()",
+    vector=True,
+    need_index=True,
+    animation_value_type="none",
+    gecko_pref="layout.css.scroll-linked-animations.enabled",
+    spec="https://drafts.csswg.org/css-animations-2/#propdef-animation-timeline",
+    rule_types_allowed=DEFAULT_RULES_EXCEPT_KEYFRAME,
+)}
+
 <% transform_extra_prefixes = "moz:layout.css.prefixes.transforms webkit" %>
 
 ${helpers.predefined_type(

components/style/properties/longhands/inherited_box.mako.rs

@@ -69,17 +69,13 @@ ${helpers.single_keyword(
 
 // According to to CSS-IMAGES-3, `optimizespeed` and `optimizequality` are synonyms for `auto`
 // And, firefox doesn't support `pixelated` yet (https://bugzilla.mozilla.org/show_bug.cgi?id=856337)
-${helpers.single_keyword(
+${helpers.predefined_type(
     "image-rendering",
-    "auto crisp-edges",
+    "ImageRendering",
+    "computed::ImageRendering::Auto",
     engines="gecko servo-2013 servo-2020",
-    extra_gecko_values="optimizespeed optimizequality",
-    extra_servo_2013_values="pixelated",
-    extra_servo_2020_values="pixelated",
-    gecko_aliases="-moz-crisp-edges=crisp-edges",
-    gecko_enum_prefix="StyleImageRendering",
-    animation_value_type="discrete",
     spec="https://drafts.csswg.org/css-images/#propdef-image-rendering",
+    animation_value_type="discrete",
 )}
 
 ${helpers.single_keyword(

components/style/properties/longhands/inherited_ui.mako.rs

@@ -104,6 +104,8 @@ ${helpers.predefined_type(
     gecko_pref="layout.css.color-scheme.enabled",
     animation_value_type="discrete",
     has_effect_on_gecko_scrollbars=False,
+    ignored_when_colors_disabled=True,
+    enabled_in="chrome",
 )}
 
 ${helpers.predefined_type(