Auto merge of #23973 - emilio:gecko-sync, r=emilio,jdm

style: Sync changes from mozilla-central.

See each individual commit for details.

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components/layout/construct.rs

@@ -1847,6 +1847,10 @@ where
             node.type_id()
         );
 
+        // FIXME(emilio): This should look at display-outside and
+        // display-inside, but there's so much stuff that goes through the
+        // generic "block" codepath (wrongly).
+        //
         // Switch on display and floatedness.
         match (display, float, positioning) {
             // `display: none` contributes no flow construction result.
@@ -1871,12 +1875,6 @@ where
                 self.set_flow_construction_result(node, construction_result)
             },
 
-            // List items contribute their own special flows.
-            (Display::ListItem, float_value, _) => {
-                let construction_result = self.build_flow_for_list_item(node, float_value);
-                self.set_flow_construction_result(node, construction_result)
-            },
-
             // Inline items that are absolutely-positioned contribute inline fragment construction
             // results with a hypothetical fragment.
             (Display::Inline, _, Position::Absolute) |
@@ -1958,7 +1956,12 @@ where
             // properties separately.
             (_, float_value, _) => {
                 let float_kind = FloatKind::from_property(float_value);
-                let construction_result = self.build_flow_for_block(node, float_kind);
+                // List items contribute their own special flows.
+                let construction_result = if display.is_list_item() {
+                    self.build_flow_for_list_item(node, float_value)
+                } else {
+                    self.build_flow_for_block(node, float_kind)
+                };
                 self.set_flow_construction_result(node, construction_result)
             },
         }

components/layout/generated_content.rs

@@ -19,7 +19,6 @@ use crate::traversal::InorderFlowTraversal;
 use script_layout_interface::wrapper_traits::PseudoElementType;
 use smallvec::SmallVec;
 use std::collections::{HashMap, LinkedList};
-use style::computed_values::display::T as Display;
 use style::computed_values::list_style_type::T as ListStyleType;
 use style::properties::ComputedValues;
 use style::selector_parser::RestyleDamage;
@@ -175,7 +174,7 @@ impl<'a, 'b> ResolveGeneratedContentFragmentMutator<'a, 'b> {
         }
 
         let mut list_style_type = fragment.style().get_list().list_style_type;
-        if fragment.style().get_box().display != Display::ListItem {
+        if !fragment.style().get_box().display.is_list_item() {
             list_style_type = ListStyleType::None
         }
 
@@ -291,7 +290,7 @@ impl<'a, 'b> ResolveGeneratedContentFragmentMutator<'a, 'b> {
 
     fn reset_and_increment_counters_as_necessary(&mut self, fragment: &mut Fragment) {
         let mut list_style_type = fragment.style().get_list().list_style_type;
-        if !self.is_block || fragment.style().get_box().display != Display::ListItem {
+        if !self.is_block || !fragment.style().get_box().display.is_list_item() {
             list_style_type = ListStyleType::None
         }
 

components/style/font_face.rs

@@ -414,16 +414,10 @@ impl Parse for Source {
 
 macro_rules! is_descriptor_enabled {
     ("font-display") => {
-        unsafe {
-            use crate::gecko_bindings::structs::mozilla;
-            mozilla::StaticPrefs::sVarCache_layout_css_font_display_enabled
-        }
+        static_prefs::pref!("layout.css.font-display.enabled")
     };
     ("font-variation-settings") => {
-        unsafe {
-            use crate::gecko_bindings::structs::mozilla;
-            mozilla::StaticPrefs::sVarCache_layout_css_font_variations_enabled != 0
-        }
+        static_prefs::pref!("layout.css.font-variations.enabled")
     };
     ($name:tt) => {
         true

components/style/gecko/media_queries.rs

@@ -213,12 +213,11 @@ impl Device {
             None => return MediaType::screen(),
         };
 
-        // Gecko allows emulating random media with mIsEmulatingMedia and
-        // mMediaEmulated.
-        let medium_to_use = if pc.mIsEmulatingMedia() != 0 {
-            pc.mMediaEmulated.mRawPtr
+        // Gecko allows emulating random media with mMediaEmulationData.mMedium.
+        let medium_to_use = if !pc.mMediaEmulationData.mMedium.mRawPtr.is_null() {
+            pc.mMediaEmulationData.mMedium.mRawPtr
         } else {
-            pc.mMedium
+            pc.mMedium as *const structs::nsAtom as *mut _
         };
 
         MediaType(CustomIdent(unsafe { Atom::from_raw(medium_to_use) }))
@@ -253,9 +252,8 @@ impl Device {
             None => return Scale::new(1.),
         };
 
-        let override_dppx = pc.mOverrideDPPX;
-        if override_dppx > 0.0 {
-            return Scale::new(override_dppx);
+        if pc.mMediaEmulationData.mDPPX > 0.0 {
+            return Scale::new(pc.mMediaEmulationData.mDPPX);
         }
 
         let au_per_dpx = pc.mCurAppUnitsPerDevPixel as f32;
@@ -270,8 +268,7 @@ impl Device {
         if doc.mIsBeingUsedAsImage() {
             return true;
         }
-        let document_color_use =
-            unsafe { structs::StaticPrefs::sVarCache_browser_display_document_color_use };
+        let document_color_use = static_prefs::pref!("browser.display.document_color_use");
         let prefs = self.pref_sheet_prefs();
         match document_color_use {
             1 => true,

components/style/gecko/pseudo_element.rs

@@ -187,9 +187,7 @@ impl PseudoElement {
             PseudoElement::FirstLine => PropertyFlags::APPLIES_TO_FIRST_LINE,
             PseudoElement::Placeholder => PropertyFlags::APPLIES_TO_PLACEHOLDER,
             PseudoElement::Cue => PropertyFlags::APPLIES_TO_CUE,
-            PseudoElement::Marker
-                if unsafe { structs::StaticPrefs::sVarCache_layout_css_marker_restricted } =>
-            {
+            PseudoElement::Marker if static_prefs::pref!("layout.css.marker.restricted") => {
                 PropertyFlags::APPLIES_TO_MARKER
             },
             _ => return None,

components/style/gecko/pseudo_element_definition.mako.rs

@@ -112,7 +112,7 @@ impl PseudoElement {
             % for pseudo in PSEUDOS:
                 ${pseudo_element_variant(pseudo)} =>
                 % if pseudo.is_tree_pseudo_element():
-                    if unsafe { structs::StaticPrefs::sVarCache_layout_css_xul_tree_pseudos_content_enabled } {
+                    if static_prefs::pref!("layout.css.xul-tree-pseudos.content.enabled") {
                         0
                     } else {
                         structs::CSS_PSEUDO_ELEMENT_ENABLED_IN_UA_SHEETS_AND_CHROME
@@ -209,9 +209,7 @@ impl PseudoElement {
                 if starts_with_ignore_ascii_case(name, "-moz-tree-") {
                     return PseudoElement::tree_pseudo_element(name, Box::new([]))
                 }
-                if unsafe {
-                    structs::StaticPrefs::sVarCache_layout_css_unknown_webkit_pseudo_element
-                } {
+                if static_prefs::pref!("layout.css.unknown-webkit-pseudo-element") {
                     const WEBKIT_PREFIX: &str = "-webkit-";
                     if starts_with_ignore_ascii_case(name, WEBKIT_PREFIX) {
                         let part = string_as_ascii_lowercase(&name[WEBKIT_PREFIX.len()..]);

components/style/gecko/selector_parser.rs

@@ -5,7 +5,7 @@
 //! Gecko-specific bits for selector-parsing.
 
 use crate::element_state::{DocumentState, ElementState};
-use crate::gecko_bindings::structs::{self, RawServoSelectorList};
+use crate::gecko_bindings::structs::RawServoSelectorList;
 use crate::gecko_bindings::sugar::ownership::{HasBoxFFI, HasFFI, HasSimpleFFI};
 use crate::invalidation::element::document_state::InvalidationMatchingData;
 use crate::selector_parser::{Direction, SelectorParser};
@@ -170,13 +170,10 @@ impl NonTSPseudoClass {
 
     /// Returns whether the pseudo-class is enabled in content sheets.
     fn is_enabled_in_content(&self) -> bool {
-        use crate::gecko_bindings::structs::mozilla;
         match *self {
             // For pseudo-classes with pref, the availability in content
             // depends on the pref.
-            NonTSPseudoClass::Fullscreen => unsafe {
-                mozilla::StaticPrefs::sVarCache_full_screen_api_unprefix_enabled
-            },
+            NonTSPseudoClass::Fullscreen => static_prefs::pref!("full-screen-api.unprefix.enabled"),
             // Otherwise, a pseudo-class is enabled in content when it
             // doesn't have any enabled flag.
             _ => !self
@@ -354,8 +351,7 @@ impl<'a, 'i> ::selectors::Parser<'i> for SelectorParser<'a> {
 
     #[inline]
     fn parse_part(&self) -> bool {
-        self.chrome_rules_enabled() ||
-            unsafe { structs::StaticPrefs::sVarCache_layout_css_shadow_parts_enabled }
+        self.chrome_rules_enabled() || static_prefs::pref!("layout.css.shadow-parts.enabled")
     }
 
     fn parse_non_ts_pseudo_class(

components/style/lib.rs

@@ -91,6 +91,8 @@ extern crate servo_config;
 extern crate servo_url;
 extern crate smallbitvec;
 extern crate smallvec;
+#[cfg(feature = "gecko")]
+extern crate static_prefs;
 #[cfg(feature = "servo")]
 extern crate string_cache;
 #[macro_use]

components/style/media_queries/media_feature_expression.rs

@@ -11,8 +11,6 @@ use super::Device;
 use crate::context::QuirksMode;
 #[cfg(feature = "gecko")]
 use crate::gecko::media_features::MEDIA_FEATURES;
-#[cfg(feature = "gecko")]
-use crate::gecko_bindings::structs;
 use crate::parser::{Parse, ParserContext};
 #[cfg(feature = "servo")]
 use crate::servo::media_queries::MEDIA_FEATURES;
@@ -301,9 +299,7 @@ impl MediaFeatureExpression {
                     if starts_with_ignore_ascii_case(feature_name, "-webkit-") {
                         feature_name = &feature_name[8..];
                         requirements.insert(ParsingRequirements::WEBKIT_PREFIX);
-                        if unsafe {
-                            structs::StaticPrefs::sVarCache_layout_css_prefixes_device_pixel_ratio_webkit
-                        } {
+                        if static_prefs::pref!("layout.css.prefixes.device-pixel-ratio-webkit") {
                             requirements.insert(
                                 ParsingRequirements::WEBKIT_DEVICE_PIXEL_RATIO_PREF_ENABLED,
                             );

components/style/properties/cascade.rs

@@ -673,15 +673,15 @@ impl<'a, 'b: 'a> Cascade<'a, 'b> {
     #[inline]
     #[cfg(feature = "gecko")]
     fn recompute_default_font_family_type_if_needed(&mut self) {
-        use crate::gecko_bindings::{bindings, structs};
+        use crate::gecko_bindings::bindings;
         use crate::values::computed::font::GenericFontFamily;
 
         if !self.seen.contains(LonghandId::XLang) &&
            !self.seen.contains(LonghandId::FontFamily) {
             return;
         }
 
-        let use_document_fonts = unsafe { structs::StaticPrefs::sVarCache_browser_display_use_document_fonts != 0 };
+        let use_document_fonts = static_prefs::pref!("browser.display.use_document_fonts") != 0;
         let builder = &mut self.context.builder;
         let (default_font_type, prioritize_user_fonts) = {
             let font = builder.get_font().gecko();

components/style/properties/data.py

@@ -652,9 +652,6 @@ def _remove_common_first_line_and_first_letter_properties(props, engine):
         props.remove("text-emphasis-position")
         props.remove("text-emphasis-style")
         props.remove("text-emphasis-color")
-        props.remove("text-decoration-skip-ink")
-        props.remove("text-decoration-thickness")
-        props.remove("text-underline-offset")
 
     props.remove("overflow-wrap")
     props.remove("text-align")