Revert "Auto merge of #17868 - ferjm:bug1380259.radial.gradients, r=xidorn"

This reverts commit ef233381cc1d6389205a57c9b2a08617880abc49, reversing
changes made to f61528d2977b11673af30e075b4556a2a30f5aaf.

This broke a bunch of tests in m-c, like:

  https://treeherder.mozilla.org/logviewer.html#?job_id=118007409&repo=autoland

3 files changed, 20 insertions, 70 deletions

diff --git a/components/style/gecko/conversions.rs b/components/style/gecko/conversions.rs
index 9e808b5c3a6..2426bef42dc 100644
--- a/components/style/gecko/conversions.rs
+++ b/components/style/gecko/conversions.rs
@@ -297,7 +297,7 @@ impl nsStyleImage {
                     Gecko_CreateGradient(gecko_shape,
                                          gecko_size,
                                          gradient.repeating,
-                                         false,
+                                         gradient.compat_mode != CompatMode::Modern,
                                          gradient.compat_mode == CompatMode::Moz,
                                          stop_count as u32)
                 };
diff --git a/components/style/values/generics/image.rs b/components/style/values/generics/image.rs
index 7b1a182d1ab..874912aeaf8 100644
--- a/components/style/values/generics/image.rs
+++ b/components/style/values/generics/image.rs
@@ -7,11 +7,10 @@
 //! [images]: https://drafts.csswg.org/css-images/#image-values
 
 use Atom;
-use cssparser::{serialize_identifier, Parser};
-use parser::{ParserContext, Parse};
-use selectors::parser::SelectorParseError;
+use cssparser::serialize_identifier;
 use std::fmt;
-use style_traits::{HasViewportPercentage, ParseError, ToCss};
+use style_traits::{HasViewportPercentage, ToCss};
+use values::computed::ComputedValueAsSpecified;
 use values::specified::url::SpecifiedUrl;
 
 /// An [image].
@@ -102,54 +101,16 @@ pub enum Ellipse<LengthOrPercentage> {
 }
 
 /// https://drafts.csswg.org/css-images/#typedef-extent-keyword
-#[derive(Clone, Copy, Debug, HasViewportPercentage, PartialEq, ToComputedValue)]
-#[cfg_attr(feature = "servo", derive(HeapSizeOf))]
-pub enum ShapeExtent {
-    /// The gradient's ending shape meets the side of the box closest to its center (for circles) or
-    /// meets both the vertical and horizontal sides closest to the center (for ellipses).
-    ClosestSide,
-    /// Similar to closest-side, except the ending shape is sized to meet the side of the box
-    /// farthest from its center (or vertical and horizontal sides).
-    FarthestSide,
-    /// The gradient's ending shape is sized so that it exactly meets the closest corner of the box
-    /// from its center.
-    ClosestCorner,
-    /// The gradient's ending shape is sized so that it exactly meets the closest corner of the box
-    /// from its center.
-    FarthestCorner,
-    /// Legacy value, equivalent to ClosestSide.
-    Contain,
-    /// Legacy value, equivalent to FarthestCorner.
-    Cover,
-}
-
-impl Parse for ShapeExtent {
-    fn parse<'i, 't>(_: &ParserContext, input: &mut Parser<'i, 't>) -> Result<Self, ParseError<'i>> {
-        let ident = input.expect_ident()?;
-        Ok(match_ignore_ascii_case! { &ident,
-            "closest-side" => ShapeExtent::ClosestSide,
-            "farthest-side" => ShapeExtent::FarthestSide,
-            "closest-corner" => ShapeExtent::ClosestCorner,
-            "farthest-corner" => ShapeExtent::FarthestCorner,
-            "contain" => ShapeExtent::ClosestSide,
-            "cover" => ShapeExtent::FarthestCorner,
-            _ => return Err(SelectorParseError::UnexpectedIdent(ident.clone()).into()),
-        })
-    }
-}
-
-impl ToCss for ShapeExtent {
-    fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-        match *self {
-            ShapeExtent::ClosestSide |
-            ShapeExtent::Contain => dest.write_str("closest-side"),
-            ShapeExtent::FarthestSide => dest.write_str("farthest-side"),
-            ShapeExtent::ClosestCorner => dest.write_str("closest-corner"),
-            ShapeExtent::FarthestCorner |
-            ShapeExtent::Cover => dest.write_str("farthest-corner"),
-        }
-    }
-}
+define_css_keyword_enum!(ShapeExtent:
+    "closest-side" => ClosestSide,
+    "farthest-side" => FarthestSide,
+    "closest-corner" => ClosestCorner,
+    "farthest-corner" => FarthestCorner,
+    "contain" => Contain,
+    "cover" => Cover
+);
+no_viewport_percentage!(ShapeExtent);
+impl ComputedValueAsSpecified for ShapeExtent {}
 
 /// A gradient item.
 /// https://drafts.csswg.org/css-images-4/#color-stop-syntax
@@ -259,12 +220,7 @@ impl<D, L, LoP, P, C, A> ToCss for Gradient<D, L, LoP, P, C, A>
 {
     fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
         match self.compat_mode {
-            CompatMode::WebKit => {
-                match self.kind {
-                    GradientKind::Radial(_, _, _) => {},
-                    _ => dest.write_str("-webkit-")?
-                }
-            },
+            CompatMode::WebKit => dest.write_str("-webkit-")?,
             CompatMode::Moz => dest.write_str("-moz-")?,
             _ => {},
         }
@@ -295,11 +251,6 @@ impl<D, L, LoP, P, C, A> ToCss for Gradient<D, L, LoP, P, C, A>
                     }
                     dest.write_str("at ")?;
                     position.to_css(dest)?;
-                } else if self.compat_mode == CompatMode::WebKit {
-                    if !omit_shape {
-                        shape.to_css(dest)?;
-                    }
-
                 } else {
                     position.to_css(dest)?;
                     if let Some(ref a) = *angle {
diff --git a/components/style/values/specified/image.rs b/components/style/values/specified/image.rs
index c8b6d45c278..840f4ed1cf3 100644
--- a/components/style/values/specified/image.rs
+++ b/components/style/values/specified/image.rs
@@ -751,7 +751,7 @@ impl EndingShape {
                      input: &mut Parser<'i, 't>,
                      compat_mode: CompatMode)
                      -> Result<Self, ParseError<'i>> {
-        if let Ok(extent) = input.try(|i| ShapeExtent::parse_with_compat_mode(context, i, compat_mode)) {
+        if let Ok(extent) = input.try(|i| ShapeExtent::parse_with_compat_mode(i, compat_mode)) {
             if input.try(|i| i.expect_ident_matching("circle")).is_ok() {
                 return Ok(GenericEndingShape::Circle(Circle::Extent(extent)));
             }
@@ -759,7 +759,7 @@ impl EndingShape {
             return Ok(GenericEndingShape::Ellipse(Ellipse::Extent(extent)));
         }
         if input.try(|i| i.expect_ident_matching("circle")).is_ok() {
-            if let Ok(extent) = input.try(|i| ShapeExtent::parse_with_compat_mode(context, i, compat_mode)) {
+            if let Ok(extent) = input.try(|i| ShapeExtent::parse_with_compat_mode(i, compat_mode)) {
                 return Ok(GenericEndingShape::Circle(Circle::Extent(extent)));
             }
             if compat_mode == CompatMode::Modern {
@@ -770,7 +770,7 @@ impl EndingShape {
             return Ok(GenericEndingShape::Circle(Circle::Extent(ShapeExtent::FarthestCorner)));
         }
         if input.try(|i| i.expect_ident_matching("ellipse")).is_ok() {
-            if let Ok(extent) = input.try(|i| ShapeExtent::parse_with_compat_mode(context, i, compat_mode)) {
+            if let Ok(extent) = input.try(|i| ShapeExtent::parse_with_compat_mode(i, compat_mode)) {
                 return Ok(GenericEndingShape::Ellipse(Ellipse::Extent(extent)));
             }
             if compat_mode == CompatMode::Modern {
@@ -828,11 +828,10 @@ impl EndingShape {
 }
 
 impl ShapeExtent {
-    fn parse_with_compat_mode<'i, 't>(context: &ParserContext,
-                                      input: &mut Parser<'i, 't>,
+    fn parse_with_compat_mode<'i, 't>(input: &mut Parser<'i, 't>,
                                       compat_mode: CompatMode)
                                       -> Result<Self, ParseError<'i>> {
-        match Self::parse(context, input)? {
+        match Self::parse(input)? {
             ShapeExtent::Contain | ShapeExtent::Cover if compat_mode == CompatMode::Modern => {
                 Err(StyleParseError::UnspecifiedError.into())
             },