Auto merge of #21787 - emilio:gecko-sync, r=emilio

style: Sync changes from mozilla-central.

See each individual commit for details.

https://bugzilla.mozilla.org/show_bug.cgi?id=1493435

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12 files changed, 160 insertions, 39 deletions

diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 1de99ec16f1..2275316bf72 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -5304,7 +5304,7 @@ clip-path
 </%self:impl_trait>
 
 <%self:impl_trait style_struct_name="InheritedUI"
-                  skip_longhands="cursor">
+                  skip_longhands="cursor scrollbar-color">
     pub fn set_cursor(&mut self, v: longhands::cursor::computed_value::T) {
         use style_traits::cursor::CursorKind;
 
@@ -5450,6 +5450,48 @@ clip-path
 
         longhands::cursor::computed_value::T { images, keyword }
     }
+
+    pub fn set_scrollbar_color(&mut self, v: longhands::scrollbar_color::computed_value::T) {
+        use gecko_bindings::structs::StyleComplexColor;
+        use values::generics::ui::ScrollbarColor;
+        match v {
+            ScrollbarColor::Auto => {
+                self.gecko.mScrollbarFaceColor = StyleComplexColor::auto();
+                self.gecko.mScrollbarTrackColor = StyleComplexColor::auto();
+            }
+            ScrollbarColor::Colors { thumb, track } => {
+                self.gecko.mScrollbarFaceColor = thumb.into();
+                self.gecko.mScrollbarTrackColor = track.into();
+            }
+        }
+    }
+
+    pub fn copy_scrollbar_color_from(&mut self, other: &Self) {
+        self.gecko.mScrollbarFaceColor = other.gecko.mScrollbarFaceColor;
+        self.gecko.mScrollbarTrackColor = other.gecko.mScrollbarTrackColor;
+    }
+
+    pub fn reset_scrollbar_color(&mut self, other: &Self) {
+        self.copy_scrollbar_color_from(other);
+    }
+
+    pub fn clone_scrollbar_color(&self) -> longhands::scrollbar_color::computed_value::T {
+        use gecko_bindings::structs::StyleComplexColor_Tag as Tag;
+        use values::generics::ui::ScrollbarColor;
+        debug_assert!(
+            (self.gecko.mScrollbarFaceColor.mTag == Tag::eAuto) ==
+            (self.gecko.mScrollbarTrackColor.mTag == Tag::eAuto),
+            "Whether the two colors are `auto` should match",
+        );
+        if self.gecko.mScrollbarFaceColor.mTag == Tag::eAuto {
+            ScrollbarColor::Auto
+        } else {
+            ScrollbarColor::Colors {
+                thumb: self.gecko.mScrollbarFaceColor.into(),
+                track: self.gecko.mScrollbarTrackColor.into(),
+            }
+        }
+    }
 </%self:impl_trait>
 
 <%self:impl_trait style_struct_name="Column"
diff --git a/components/style/properties/longhands/inherited_ui.mako.rs b/components/style/properties/longhands/inherited_ui.mako.rs
index 0b2b590cf7f..6bdd0ff51b5 100644
--- a/components/style/properties/longhands/inherited_ui.mako.rs
+++ b/components/style/properties/longhands/inherited_ui.mako.rs
@@ -67,24 +67,15 @@ ${helpers.predefined_type(
     products="gecko",
 )}
 
-// Only scrollbar-face-color and scrollbar-track-color are added here.
-// These two are the only common parts of scrollbar among Windows and
-// macOS. We may or may not want to provide other properties to allow
-// finer-grain control.
-//
-// NOTE The syntax in spec is currently `normal | <color>`, but I think
-//      reusing `auto | <color>` as `caret-color` makes more sense. See
-//      https://github.com/w3c/csswg-drafts/issues/2660
-% for part in ["face", "track"]:
 ${helpers.predefined_type(
-    "scrollbar-%s-color" % part,
-    "ColorOrAuto",
-    "Either::Second(Auto)",
-    spec="https://drafts.csswg.org/css-scrollbars-1/#scrollbar-color-properties",
+    "scrollbar-color",
+    "ui::ScrollbarColor",
+    "Default::default()",
+    spec="https://drafts.csswg.org/css-scrollbars-1/#scrollbar-color",
     gecko_pref="layout.css.scrollbar-colors.enabled",
-    animation_value_type="ColorOrAuto",
+    animation_value_type="ScrollbarColor",
+    boxed=True,
     ignored_when_colors_disabled=True,
     enabled_in="chrome",
     products="gecko",
 )}
-% endfor
diff --git a/components/style/properties/longhands/svg.mako.rs b/components/style/properties/longhands/svg.mako.rs
index 36105247676..acdb809135f 100644
--- a/components/style/properties/longhands/svg.mako.rs
+++ b/components/style/properties/longhands/svg.mako.rs
@@ -183,6 +183,7 @@ ${helpers.predefined_type(
     "ImageLayer",
     "Either::First(None_)",
     initial_specified_value="Either::First(None_)",
+    parse_method="parse_with_cors_anonymous",
     spec="https://drafts.fxtf.org/css-masking/#propdef-mask-image",
     vector=True,
     products="gecko",
diff --git a/components/style/properties/shorthands/box.mako.rs b/components/style/properties/shorthands/box.mako.rs
index 960e608cea7..3886c7d2d3c 100644
--- a/components/style/properties/shorthands/box.mako.rs
+++ b/components/style/properties/shorthands/box.mako.rs
@@ -7,7 +7,7 @@
 <%helpers:shorthand
     name="overflow"
     flags="SHORTHAND_IN_GETCS"
-    sub_properties="overflow-y overflow-x"
+    sub_properties="overflow-x overflow-y"
     spec="https://drafts.csswg.org/css-overflow/#propdef-overflow"
 >
     use properties::longhands::overflow_x::parse as parse_overflow;
@@ -52,9 +52,9 @@
                 }
             }
         % endif
-        let overflow_y = parse_overflow(context, input)?;
-        let overflow_x =
-            input.try(|i| parse_overflow(context, i)).unwrap_or(overflow_y);
+        let overflow_x = parse_overflow(context, input)?;
+        let overflow_y =
+            input.try(|i| parse_overflow(context, i)).unwrap_or(overflow_x);
         Ok(expanded! {
             overflow_x: overflow_x,
             overflow_y: overflow_y,
@@ -63,10 +63,10 @@
 
     impl<'a> ToCss for LonghandsToSerialize<'a>  {
         fn to_css<W>(&self, dest: &mut CssWriter<W>) -> fmt::Result where W: fmt::Write {
-            self.overflow_y.to_css(dest)?;
+            self.overflow_x.to_css(dest)?;
             if self.overflow_x != self.overflow_y {
                 dest.write_char(' ')?;
-                self.overflow_x.to_css(dest)?;
+                self.overflow_y.to_css(dest)?;
             }
             Ok(())
         }
diff --git a/components/style/values/computed/font.rs b/components/style/values/computed/font.rs
index 2c3d2853e5c..4cb8f7a7bdf 100644
--- a/components/style/values/computed/font.rs
+++ b/components/style/values/computed/font.rs
@@ -483,16 +483,19 @@ impl SingleFontFamily {
             FontFamilyType::eFamily_fantasy => SingleFontFamily::Generic(atom!("fantasy")),
             FontFamilyType::eFamily_moz_fixed => SingleFontFamily::Generic(atom!("-moz-fixed")),
             FontFamilyType::eFamily_named => {
-                let name = Atom::from(&*family.mName);
+                let name = unsafe { Atom::from_raw(family.mName.mRawPtr) };
                 SingleFontFamily::FamilyName(FamilyName {
                     name,
                     syntax: FamilyNameSyntax::Identifiers,
                 })
             },
-            FontFamilyType::eFamily_named_quoted => SingleFontFamily::FamilyName(FamilyName {
-                name: (&*family.mName).into(),
-                syntax: FamilyNameSyntax::Quoted,
-            }),
+            FontFamilyType::eFamily_named_quoted => {
+                let name = unsafe { Atom::from_raw(family.mName.mRawPtr) };
+                SingleFontFamily::FamilyName(FamilyName {
+                    name,
+                    syntax: FamilyNameSyntax::Quoted,
+                })
+            },
             _ => panic!("Found unexpected font FontFamilyType"),
         }
     }
@@ -538,9 +541,15 @@ impl Hash for FontFamilyList {
     where
         H: Hasher,
     {
+        use string_cache::WeakAtom;
+
         for name in self.0.mNames.iter() {
             name.mType.hash(state);
-            name.mName.hash(state);
+            if !name.mName.mRawPtr.is_null() {
+                unsafe {
+                    WeakAtom::new(name.mName.mRawPtr).hash(state);
+                }
+            }
         }
     }
 }
@@ -552,7 +561,7 @@ impl PartialEq for FontFamilyList {
             return false;
         }
         for (a, b) in self.0.mNames.iter().zip(other.0.mNames.iter()) {
-            if a.mType != b.mType || &*a.mName != &*b.mName {
+            if a.mType != b.mType || a.mName.mRawPtr != b.mName.mRawPtr {
                 return false;
             }
         }
diff --git a/components/style/values/computed/ui.rs b/components/style/values/computed/ui.rs
index 5307f79a38e..40f1a378cc9 100644
--- a/components/style/values/computed/ui.rs
+++ b/components/style/values/computed/ui.rs
@@ -20,3 +20,6 @@ pub type Cursor = generics::Cursor<CursorImage>;
 
 /// A computed value for item of `image cursors`.
 pub type CursorImage = generics::CursorImage<ComputedImageUrl, Number>;
+
+/// A computed value for `scrollbar-color` property.
+pub type ScrollbarColor = generics::ScrollbarColor<Color>;
diff --git a/components/style/values/generics/ui.rs b/components/style/values/generics/ui.rs
index bef1926bc90..73f050bb12a 100644
--- a/components/style/values/generics/ui.rs
+++ b/components/style/values/generics/ui.rs
@@ -67,3 +67,27 @@ impl<ImageUrl: ToCss, Number: ToCss> ToCss for CursorImage<ImageUrl, Number> {
         Ok(())
     }
 }
+
+/// A generic value for `scrollbar-color` property.
+///
+/// https://drafts.csswg.org/css-scrollbars-1/#scrollbar-color
+#[derive(Animate, Clone, ComputeSquaredDistance, Copy, Debug, MallocSizeOf, PartialEq,
+         SpecifiedValueInfo, ToAnimatedValue, ToAnimatedZero, ToComputedValue, ToCss)]
+pub enum ScrollbarColor<Color> {
+    /// `auto`
+    Auto,
+    /// `<color>{2}`
+    Colors {
+        /// First `<color>`, for color of the scrollbar thumb.
+        thumb: Color,
+        /// Second `<color>`, for color of the scrollbar track.
+        track: Color,
+    }
+}
+
+impl<Color> Default for ScrollbarColor<Color> {
+    #[inline]
+    fn default() -> Self {
+        ScrollbarColor::Auto
+    }
+}
diff --git a/components/style/values/specified/image.rs b/components/style/values/specified/image.rs
index 1b080816e83..b1a611846a8 100644
--- a/components/style/values/specified/image.rs
+++ b/components/style/values/specified/image.rs
@@ -33,6 +33,20 @@ use values::specified::url::SpecifiedImageUrl;
 /// A specified image layer.
 pub type ImageLayer = Either<None_, Image>;
 
+impl ImageLayer {
+    /// This is a specialization of Either with an alternative parse
+    /// method to provide anonymous CORS headers for the Image url fetch.
+    pub fn parse_with_cors_anonymous<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Self, ParseError<'i>> {
+        if let Ok(v) = input.try(|i| None_::parse(context, i)) {
+            return Ok(Either::First(v));
+        }
+        Image::parse_with_cors_anonymous(context, input).map(Either::Second)
+    }
+}
+
 /// Specified values for an image according to CSS-IMAGES.
 /// <https://drafts.csswg.org/css-images/#image-values>
 pub type Image = generic::Image<Gradient, MozImageRect, SpecifiedImageUrl>;
diff --git a/components/style/values/specified/svg_path.rs b/components/style/values/specified/svg_path.rs
index 5d397558d25..3f1fdc39d97 100644
--- a/components/style/values/specified/svg_path.rs
+++ b/components/style/values/specified/svg_path.rs
@@ -13,7 +13,7 @@ use std::slice;
 use style_traits::{CssWriter, ParseError, StyleParseErrorKind, ToCss};
 use style_traits::values::SequenceWriter;
 use values::CSSFloat;
-use values::animated::{Animate, Procedure};
+use values::animated::{Animate, Procedure, ToAnimatedZero};
 use values::distance::{ComputeSquaredDistance, SquaredDistance};
 
 /// The SVG path data.
@@ -198,9 +198,7 @@ pub enum PathCommand {
         rx: CSSFloat,
         ry: CSSFloat,
         angle: CSSFloat,
-        #[animation(constant)]
         large_arc_flag: ArcFlag,
-        #[animation(constant)]
         sweep_flag: ArcFlag,
         point: CoordPair,
         absolute: IsAbsolute,
@@ -538,6 +536,34 @@ impl ToCss for ArcFlag {
     }
 }
 
+impl Animate for ArcFlag {
+    #[inline]
+    fn animate(&self, other: &Self, procedure: Procedure) -> Result<Self, ()> {
+        (self.0 as i32)
+            .animate(&(other.0 as i32), procedure)
+            .map(|v| ArcFlag(v > 0))
+    }
+}
+
+impl ComputeSquaredDistance for ArcFlag {
+    #[inline]
+    fn compute_squared_distance(&self, other: &Self) -> Result<SquaredDistance, ()> {
+        (self.0 as i32).compute_squared_distance(&(other.0 as i32))
+    }
+}
+
+impl ToAnimatedZero for ArcFlag {
+    #[inline]
+    fn to_animated_zero(&self) -> Result<Self, ()> {
+        // The 2 ArcFlags in EllipticalArc determine which one of the 4 different arcs will be
+        // used. (i.e. From 4 combinations). In other words, if we change the flag, we get a
+        // different arc. Therefore, we return *self.
+        // https://svgwg.org/svg2-draft/paths.html#PathDataEllipticalArcCommands
+        Ok(*self)
+    }
+}
+
+
 /// SVG Path parser.
 struct PathParser<'a> {
     chars: Peekable<Cloned<slice::Iter<'a, u8>>>,
diff --git a/components/style/values/specified/ui.rs b/components/style/values/specified/ui.rs
index 7dc1e0fe1d3..c9c5c0a8414 100644
--- a/components/style/values/specified/ui.rs
+++ b/components/style/values/specified/ui.rs
@@ -122,3 +122,21 @@ impl From<MozForceBrokenImageIcon> for u8 {
         }
     }
 }
+
+/// A specified value for `scrollbar-color` property
+pub type ScrollbarColor = generics::ScrollbarColor<Color>;
+
+impl Parse for ScrollbarColor {
+    fn parse<'i, 't>(
+        context: &ParserContext,
+        input: &mut Parser<'i, 't>,
+    ) -> Result<Self, ParseError<'i>> {
+        if input.try(|i| i.expect_ident_matching("auto")).is_ok() {
+            return Ok(generics::ScrollbarColor::Auto);
+        }
+        Ok(generics::ScrollbarColor::Colors {
+            thumb: Color::parse(context, input)?,
+            track: Color::parse(context, input)?,
+        })
+    }
+}
diff --git a/tests/wpt/metadata/css/cssom/overflow-serialization.html.ini b/tests/wpt/metadata/css/cssom/overflow-serialization.html.ini
deleted file mode 100644
index 3a51b8caa02..00000000000
--- a/tests/wpt/metadata/css/cssom/overflow-serialization.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[overflow-serialization.html]
-  [CSSOM - Overflow shorthand serialization]
-    expected: FAIL
-
diff --git a/tests/wpt/metadata/css/cssom/shorthand-values.html.ini b/tests/wpt/metadata/css/cssom/shorthand-values.html.ini
index 427f39aa3e7..e0b5a48bdb5 100644
--- a/tests/wpt/metadata/css/cssom/shorthand-values.html.ini
+++ b/tests/wpt/metadata/css/cssom/shorthand-values.html.ini
@@ -29,6 +29,3 @@
   [The serialization of list-style-type: circle; list-style-position: inside; list-style-image: initial; should be canonical.]
     expected: FAIL
 
-  [The serialization of overflow-x: scroll; overflow-y: hidden; should be canonical.]
-    expected: FAIL
-