style: Remove HasViewportPercentage.

It's not needed since #18268

components/style/properties/helpers.mako.rs

@@ -83,8 +83,6 @@
         #[allow(unused_imports)]
         use smallvec::SmallVec;
         use std::fmt;
-        #[allow(unused_imports)]
-        use style_traits::HasViewportPercentage;
         use style_traits::{Separator, ToCss};
 
         pub mod single_value {
@@ -179,7 +177,7 @@
         }
 
         /// The specified value of ${name}.
-        #[derive(Clone, Debug, HasViewportPercentage, PartialEq)]
+        #[derive(Clone, Debug, PartialEq)]
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
         pub struct SpecifiedValue(pub Vec<single_value::SpecifiedValue>);
 
@@ -420,7 +418,6 @@
     %>
     <%call expr="longhand(name, keyword=Keyword(name, values, **keyword_kwargs), **kwargs)">
         use properties::longhands::system_font::SystemFont;
-        no_viewport_percentage!(SpecifiedValue);
 
         pub mod computed_value {
             use cssparser::Parser;
@@ -529,7 +526,6 @@
             impl ComputedValueAsSpecified for SpecifiedValue {}
         % endif
 
-        no_viewport_percentage!(SpecifiedValue);
     </%call>
 </%def>
 
@@ -948,7 +944,7 @@
         }
 
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-        #[derive(Clone, Debug, HasViewportPercentage, PartialEq, ToCss)]
+        #[derive(Clone, Debug, PartialEq, ToCss)]
         pub struct SpecifiedValue(pub ${length_type});
 
         % if length_type == "MozLength":

components/style/properties/helpers/animated_properties.mako.rs

@@ -214,7 +214,6 @@ pub enum TransitionProperty {
     Unsupported(CustomIdent)
 }
 
-no_viewport_percentage!(TransitionProperty);
 
 impl ComputedValueAsSpecified for TransitionProperty {}
 

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

@@ -69,7 +69,6 @@ ${helpers.predefined_type("background-image", "ImageLayer",
         pub struct T(pub RepeatKeyword, pub RepeatKeyword);
     }
 
-    no_viewport_percentage!(SpecifiedValue);
 
     impl ToCss for computed_value::T {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {

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

@@ -78,7 +78,6 @@ ${helpers.gecko_keyword_conversion(Keyword('border-style',
         use std::fmt;
         use style_traits::ToCss;
         use values::specified::RGBAColor;
-        no_viewport_percentage!(SpecifiedValue);
 
         pub mod computed_value {
             use cssparser::RGBA;
@@ -230,7 +229,6 @@ ${helpers.predefined_type("border-image-outset", "LengthOrNumberRect",
                    spec="https://drafts.csswg.org/css-backgrounds/#border-image-repeat">
     use style_traits::ToCss;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         pub use super::RepeatKeyword;

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

@@ -36,7 +36,6 @@
     %>
     use values::computed::ComputedValueAsSpecified;
     use style_traits::ToCss;
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         pub use super::SpecifiedValue as T;
@@ -222,7 +221,6 @@ ${helpers.single_keyword("position", "static absolute relative fixed",
                                   gecko_pref_ident="float_"
                                   flags="APPLIES_TO_FIRST_LETTER"
                                   spec="https://drafts.csswg.org/css-box/#propdef-float">
-    no_viewport_percentage!(SpecifiedValue);
     impl ToComputedValue for SpecifiedValue {
         type ComputedValue = computed_value::T;
 
@@ -261,7 +259,6 @@ ${helpers.single_keyword("position", "static absolute relative fixed",
                                   gecko_enum_prefix="StyleClear"
                                   gecko_ffi_name="mBreakType"
                                   spec="https://www.w3.org/TR/CSS2/visuren.html#flow-control">
-    no_viewport_percentage!(SpecifiedValue);
     impl ToComputedValue for SpecifiedValue {
         type ComputedValue = computed_value::T;
 
@@ -327,7 +324,7 @@ ${helpers.single_keyword("position", "static absolute relative fixed",
 
     /// The `vertical-align` value.
     #[allow(non_camel_case_types)]
-    #[derive(Clone, Debug, HasViewportPercentage, PartialEq)]
+    #[derive(Clone, Debug, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     pub enum SpecifiedValue {
         % for keyword in vertical_align_keywords:
@@ -571,7 +568,6 @@ ${helpers.predefined_type("transition-delay",
             }
         }
     }
-    no_viewport_percentage!(SpecifiedValue);
 
     pub fn parse<'i, 't>(context: &ParserContext, input: &mut Parser<'i, 't>)
                          -> Result<SpecifiedValue,ParseError<'i>> {
@@ -641,7 +637,6 @@ ${helpers.predefined_type("animation-timing-function",
         }
     }
 
-    no_viewport_percentage!(SpecifiedValue);
 
     #[inline]
     pub fn get_initial_value() -> computed_value::T {
@@ -842,7 +837,7 @@ ${helpers.predefined_type(
     /// Multiple transform functions compose a transformation.
     ///
     /// Some transformations can be expressed by other more general functions.
-    #[derive(Clone, Debug, HasViewportPercentage, PartialEq)]
+    #[derive(Clone, Debug, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     pub enum SpecifiedOperation {
         /// Represents a 2D 2x3 matrix.
@@ -991,7 +986,7 @@ ${helpers.predefined_type(
         }
     }
 
-    #[derive(Clone, Debug, HasViewportPercentage, PartialEq)]
+    #[derive(Clone, Debug, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     pub struct SpecifiedValue(Vec<SpecifiedOperation>);
 
@@ -1705,7 +1700,6 @@ ${helpers.predefined_type("transform-origin",
     use values::computed::ComputedValueAsSpecified;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         pub type T = super::SpecifiedValue;
@@ -1850,7 +1844,6 @@ ${helpers.single_keyword("-moz-orient",
     use values::computed::ComputedValueAsSpecified;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         pub use super::SpecifiedValue as T;
@@ -1924,7 +1917,6 @@ ${helpers.predefined_type(
     use values::computed::ComputedValueAsSpecified;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         pub use super::SpecifiedValue as T;

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

@@ -34,7 +34,6 @@
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     #[derive(Clone, Debug, PartialEq, ToCss)]
     pub struct SpecifiedValue(pub Color);
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         use cssparser;

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

@@ -23,7 +23,6 @@
     pub use self::computed_value::ContentItem;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         use cssparser;
@@ -296,7 +295,6 @@
         computed_value::T(Vec::new())
     }
 
-    no_viewport_percentage!(SpecifiedValue);
 
     impl ToCss for SpecifiedValue {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result

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

@@ -76,7 +76,6 @@ macro_rules! impl_gecko_keyword_conversions {
     use std::fmt;
     use style_traits::ToCss;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         use cssparser::{CssStringWriter, Parser, serialize_identifier};
@@ -430,7 +429,6 @@ ${helpers.single_keyword_system("font-variant-caps",
                    spec="https://drafts.csswg.org/css-fonts/#propdef-font-weight">
     use properties::longhands::system_font::SystemFont;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     #[derive(Clone, Copy, Debug, Eq, PartialEq, ToCss)]
@@ -597,7 +595,7 @@ ${helpers.single_keyword_system("font-variant-caps",
     use app_units::Au;
     use properties::longhands::system_font::SystemFont;
     use std::fmt;
-    use style_traits::{HasViewportPercentage, ToCss};
+    use style_traits::ToCss;
     use values::FONT_MEDIUM_PX;
     use values::computed::NonNegativeAu;
     use values::specified::{AllowQuirks, FontRelativeLength, LengthOrPercentage, NoCalcLength};
@@ -615,15 +613,6 @@ ${helpers.single_keyword_system("font-variant-caps",
         }
     }
 
-    impl HasViewportPercentage for SpecifiedValue {
-        fn has_viewport_percentage(&self) -> bool {
-            match *self {
-                SpecifiedValue::Length(ref lop) => lop.has_viewport_percentage(),
-                _ => false
-            }
-        }
-    }
-
     #[derive(Clone, Debug, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     pub enum SpecifiedValue {
@@ -1068,7 +1057,6 @@ ${helpers.single_keyword_system("font-variant-caps",
                    spec="https://drafts.csswg.org/css-fonts/#propdef-font-size-adjust">
     use properties::longhands::system_font::SystemFont;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     #[derive(Clone, Copy, Debug, PartialEq, ToCss)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
@@ -1190,7 +1178,6 @@ ${helpers.single_keyword_system("font-variant-caps",
     use values::computed::ComputedValueAsSpecified;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         pub use super::SpecifiedValue as T;
@@ -1302,7 +1289,6 @@ ${helpers.single_keyword_system("font-kerning",
     use style_traits::ToCss;
     use values::CustomIdent;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     #[derive(Clone, Debug, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
@@ -1512,7 +1498,6 @@ macro_rules! exclusive_value {
     use std::fmt;
     use style_traits::ToCss;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     bitflags! {
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
@@ -1658,7 +1643,6 @@ macro_rules! exclusive_value {
     use std::fmt;
     use style_traits::ToCss;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     bitflags! {
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
@@ -1818,7 +1802,6 @@ macro_rules! exclusive_value {
     use std::fmt;
     use style_traits::ToCss;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     bitflags! {
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
@@ -1981,7 +1964,6 @@ ${helpers.single_keyword_system("font-variant-position",
         Value(computed_value::T),
         System(SystemFont)
     }
-    no_viewport_percentage!(SpecifiedValue);
 
     <%self:simple_system_boilerplate name="font_feature_settings"></%self:simple_system_boilerplate>
 
@@ -2023,7 +2005,6 @@ https://drafts.csswg.org/css-fonts-4/#low-level-font-variation-settings-control-
 
     pub type SpecifiedValue = computed_value::T;
 
-    no_viewport_percentage!(SpecifiedValue);
 
 
     pub mod computed_value {
@@ -2051,7 +2032,6 @@ https://drafts.csswg.org/css-fonts-4/#low-level-font-variation-settings-control-
     use std::fmt;
     use style_traits::ToCss;
     use byteorder::{BigEndian, ByteOrder};
-    no_viewport_percentage!(SpecifiedValue);
 
     #[derive(Clone, Debug, Eq, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
@@ -2209,7 +2189,6 @@ https://drafts.csswg.org/css-fonts-4/#low-level-font-variation-settings-control-
     pub use self::computed_value::T as SpecifiedValue;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         use Atom;
@@ -2269,7 +2248,6 @@ https://drafts.csswg.org/css-fonts-4/#low-level-font-variation-settings-control-
     use std::fmt;
     use style_traits::ToCss;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         pub type T = i8;
@@ -2369,7 +2347,7 @@ ${helpers.single_keyword("-moz-math-variant",
     use gecko_bindings::structs::NS_MATHML_DEFAULT_SCRIPT_MIN_SIZE_PT;
     use values::specified::length::{AU_PER_PT, FontBaseSize, NoCalcLength};
 
-    #[derive(Clone, Debug, HasViewportPercentage, PartialEq, ToCss)]
+    #[derive(Clone, Debug, PartialEq, ToCss)]
     pub struct SpecifiedValue(pub NoCalcLength);
 
     pub mod computed_value {
@@ -2418,7 +2396,6 @@ ${helpers.single_keyword("-moz-math-variant",
     pub use self::computed_value::T as SpecifiedValue;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         use std::fmt;

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

@@ -66,7 +66,6 @@ ${helpers.single_keyword("image-rendering",
     use style_traits::ToCss;
     use values::specified::Angle;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     use std::f64::consts::PI;
     const TWO_PI: f64 = 2.0 * PI;
@@ -259,7 +258,6 @@ ${helpers.single_keyword("image-rendering",
     use style_traits::ToCss;
     use values::computed::ComputedValueAsSpecified;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     #[derive(Clone, Copy, Debug, Eq, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf, Deserialize, Serialize))]

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

@@ -259,7 +259,6 @@ ${helpers.predefined_type("marker-end", "UrlOrNone", "Either::Second(None_)",
         }
     }
 
-    no_viewport_percentage!(SpecifiedValue);
 
     impl ComputedValueAsSpecified for SpecifiedValue { }
 </%helpers:longhand>
@@ -271,7 +270,6 @@ ${helpers.predefined_type("marker-end", "UrlOrNone", "Either::Second(None_)",
     use values::CustomIdent;
     use values::computed::ComputedValueAsSpecified;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     impl ComputedValueAsSpecified for SpecifiedValue { }
 

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

@@ -60,7 +60,7 @@ ${helpers.single_keyword("caption-side", "top bottom",
     }
 
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-    #[derive(Clone, Debug, HasViewportPercentage, PartialEq, ToCss)]
+    #[derive(Clone, Debug, PartialEq, ToCss)]
     pub struct SpecifiedValue {
         pub horizontal: NonNegativeLength,
         pub vertical: Option<NonNegativeLength>,

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

@@ -70,7 +70,6 @@ ${helpers.single_keyword("word-break",
                                   animation_value_type="discrete"
                                   flags="APPLIES_TO_PLACEHOLDER",
                                   spec="https://drafts.csswg.org/css-text/#propdef-text-justify">
-    no_viewport_percentage!(SpecifiedValue);
 
     impl ToComputedValue for SpecifiedValue {
         type ComputedValue = computed_value::T;
@@ -114,7 +113,6 @@ ${helpers.single_keyword("text-align-last",
 <%helpers:longhand name="text-align" animation_value_type="discrete"
                    flags="APPLIES_TO_PLACEHOLDER"
                    spec="https://drafts.csswg.org/css-text/#propdef-text-align">
-    no_viewport_percentage!(SpecifiedValue);
     pub mod computed_value {
         use style_traits::ToCss;
         macro_rules! define_text_align {
@@ -292,7 +290,6 @@ ${helpers.predefined_type("word-spacing",
     use values::computed::ComputedValueAsSpecified;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     #[derive(Clone, Copy, Debug, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
@@ -379,7 +376,6 @@ ${helpers.predefined_type("word-spacing",
                                   spec="https://drafts.csswg.org/css-text/#propdef-white-space">
     use values::computed::ComputedValueAsSpecified;
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     % if product != "gecko":
     impl SpecifiedValue {
@@ -435,7 +431,6 @@ ${helpers.predefined_type(
     use style_traits::ToCss;
     use unicode_segmentation::UnicodeSegmentation;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
@@ -638,7 +633,6 @@ ${helpers.predefined_type(
     }
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub fn get_initial_value() -> computed_value::T {
         SpecifiedValue(HorizontalWritingModeValue::Over, VerticalWritingModeValue::Right)

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

@@ -50,7 +50,6 @@ ${helpers.single_keyword("list-style-position", "outside inside", animation_valu
         }
 
         impl ComputedValueAsSpecified for SpecifiedValue {}
-        no_viewport_percentage!(SpecifiedValue);
 
         #[cfg(feature = "gecko")]
         impl SpecifiedValue {
@@ -116,7 +115,6 @@ ${helpers.single_keyword("list-style-position", "outside inside", animation_valu
 
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     #[inline]
     pub fn get_initial_value() -> computed_value::T {
@@ -157,7 +155,6 @@ ${helpers.single_keyword("list-style-position", "outside inside", animation_valu
     }
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     impl ToCss for SpecifiedValue {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {

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

@@ -14,7 +14,6 @@
     use values::specified::url::SpecifiedUrl;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         #[cfg(feature = "gecko")]

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

@@ -311,7 +311,6 @@ ${helpers.predefined_type("object-position",
         }
     }
 
-    no_viewport_percentage!(SpecifiedValue);
     impl ComputedValueAsSpecified for SpecifiedValue {}
 
     impl ToCss for computed_value::T {
@@ -454,7 +453,6 @@ ${helpers.predefined_type("object-position",
         pub columns: Range<u32>,
     }
 
-    no_viewport_percentage!(TemplateAreas);
     impl ComputedValueAsSpecified for TemplateAreas {}
 
     impl Parse for TemplateAreas {

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

@@ -17,7 +17,6 @@ ${helpers.single_keyword("table-layout", "auto fixed",
     use values::computed::ComputedValueAsSpecified;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
     pub type SpecifiedValue = computed_value::T;
     pub mod computed_value {
         use std::fmt;

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

@@ -18,7 +18,6 @@
     use std::fmt;
     use style_traits::ToCss;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
     #[derive(Clone, Debug, Eq, PartialEq, ToCss)]
@@ -150,7 +149,6 @@ ${helpers.single_keyword("unicode-bidi",
     use values::computed::ComputedValueAsSpecified;
 
     impl ComputedValueAsSpecified for SpecifiedValue {}
-    no_viewport_percentage!(SpecifiedValue);
 
     bitflags! {
         #[cfg_attr(feature = "servo", derive(HeapSizeOf))]

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

@@ -51,7 +51,6 @@ ${helpers.single_keyword("-moz-window-shadow", "none default menu tooltip sheet"
     use style_traits::ToCss;
     use values::computed::ComputedValueAsSpecified;
 
-    no_viewport_percentage!(SpecifiedValue);
 
     pub mod computed_value {
         #[derive(Clone, Copy, Debug, PartialEq)]

components/style/properties/properties.mako.rs

@@ -36,7 +36,7 @@ use selector_parser::PseudoElement;
 use selectors::parser::SelectorParseError;
 #[cfg(feature = "servo")] use servo_config::prefs::PREFS;
 use shared_lock::StylesheetGuards;
-use style_traits::{PARSING_MODE_DEFAULT, HasViewportPercentage, ToCss, ParseError};
+use style_traits::{PARSING_MODE_DEFAULT, ToCss, ParseError};
 use style_traits::{PropertyDeclarationParseError, StyleParseError, ValueParseError};
 use stylesheets::{CssRuleType, MallocSizeOf, MallocSizeOfFn, Origin, UrlExtraData};
 #[cfg(feature = "servo")] use values::Either;
@@ -873,19 +873,6 @@ impl UnparsedValue {
     }
 }
 
-impl<'a, T: HasViewportPercentage> HasViewportPercentage for DeclaredValue<'a, T> {
-    fn has_viewport_percentage(&self) -> bool {
-        match *self {
-            DeclaredValue::Value(ref v) => v.has_viewport_percentage(),
-            DeclaredValue::WithVariables(_) => {
-                panic!("DeclaredValue::has_viewport_percentage without \
-                        resolving variables!")
-            },
-            DeclaredValue::CSSWideKeyword(_) => false,
-        }
-    }
-}
-
 impl<'a, T: ToCss> ToCss for DeclaredValue<'a, T> {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result
         where W: fmt::Write,
@@ -1299,26 +1286,6 @@ pub enum PropertyDeclaration {
     Custom(::custom_properties::Name, DeclaredValueOwned<Box<::custom_properties::SpecifiedValue>>),
 }
 
-impl HasViewportPercentage for PropertyDeclaration {
-    fn has_viewport_percentage(&self) -> bool {
-        match *self {
-            % for property in data.longhands:
-                PropertyDeclaration::${property.camel_case}(ref val) => {
-                    val.has_viewport_percentage()
-                },
-            % endfor
-            PropertyDeclaration::WithVariables(..) => {
-                panic!("DeclaredValue::has_viewport_percentage without \
-                        resolving variables!")
-            },
-            PropertyDeclaration::CSSWideKeyword(..) => false,
-            PropertyDeclaration::Custom(_, ref val) => {
-                val.borrow().has_viewport_percentage()
-            }
-        }
-    }
-}
-
 impl fmt::Debug for PropertyDeclaration {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         self.id().to_css(f)?;