Auto merge of #23464 - kleinph:layout-type-alias-enums, r=jdm

Use type alias enums in layout code

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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #22862 (GitHub issue number if applicable)

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because tests should already be there and no functional changes are made.

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2 files changed, 17 insertions, 24 deletions

diff --git a/components/layout/display_list/conversions.rs b/components/layout/display_list/conversions.rs
index f49c37e7f91..f541ef581ac 100644
--- a/components/layout/display_list/conversions.rs
+++ b/components/layout/display_list/conversions.rs
@@ -8,7 +8,6 @@ use style::computed_values::image_rendering::T as ImageRendering;
 use style::computed_values::mix_blend_mode::T as MixBlendMode;
 use style::computed_values::transform_style::T as TransformStyle;
 use style::values::computed::{BorderStyle, Filter};
-use style::values::generics::effects::Filter as GenericFilter;
 use style::values::specified::border::BorderImageRepeatKeyword;
 use style::values::RGBA;
 use webrender_api as wr;
@@ -40,19 +39,19 @@ impl ToLayout for Filter {
     type Type = wr::FilterOp;
     fn to_layout(&self) -> Self::Type {
         match *self {
-            GenericFilter::Blur(radius) => wr::FilterOp::Blur(radius.px()),
-            GenericFilter::Brightness(amount) => wr::FilterOp::Brightness(amount.0),
-            GenericFilter::Contrast(amount) => wr::FilterOp::Contrast(amount.0),
-            GenericFilter::Grayscale(amount) => wr::FilterOp::Grayscale(amount.0),
-            GenericFilter::HueRotate(angle) => wr::FilterOp::HueRotate(angle.radians()),
-            GenericFilter::Invert(amount) => wr::FilterOp::Invert(amount.0),
-            GenericFilter::Opacity(amount) => wr::FilterOp::Opacity(amount.0.into(), amount.0),
-            GenericFilter::Saturate(amount) => wr::FilterOp::Saturate(amount.0),
-            GenericFilter::Sepia(amount) => wr::FilterOp::Sepia(amount.0),
+            Filter::Blur(radius) => wr::FilterOp::Blur(radius.px()),
+            Filter::Brightness(amount) => wr::FilterOp::Brightness(amount.0),
+            Filter::Contrast(amount) => wr::FilterOp::Contrast(amount.0),
+            Filter::Grayscale(amount) => wr::FilterOp::Grayscale(amount.0),
+            Filter::HueRotate(angle) => wr::FilterOp::HueRotate(angle.radians()),
+            Filter::Invert(amount) => wr::FilterOp::Invert(amount.0),
+            Filter::Opacity(amount) => wr::FilterOp::Opacity(amount.0.into(), amount.0),
+            Filter::Saturate(amount) => wr::FilterOp::Saturate(amount.0),
+            Filter::Sepia(amount) => wr::FilterOp::Sepia(amount.0),
             // Statically check that DropShadow is impossible.
-            GenericFilter::DropShadow(ref shadow) => match *shadow {},
+            Filter::DropShadow(ref shadow) => match *shadow {},
             // Statically check that Url is impossible.
-            GenericFilter::Url(ref url) => match *url {},
+            Filter::Url(ref url) => match *url {},
         }
     }
 }
diff --git a/components/layout/display_list/gradient.rs b/components/layout/display_list/gradient.rs
index 9b19ee48299..264bea7fbee 100644
--- a/components/layout/display_list/gradient.rs
+++ b/components/layout/display_list/gradient.rs
@@ -2,16 +2,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
 
-// FIXME(rust-lang/rust#26264): Remove GenericEndingShape and GenericGradientItem.
-
 use crate::display_list::ToLayout;
 use app_units::Au;
 use euclid::{Point2D, Size2D, Vector2D};
 use style::properties::ComputedValues;
 use style::values::computed::image::{EndingShape, LineDirection};
 use style::values::computed::{Angle, GradientItem, LengthPercentage, Percentage, Position};
-use style::values::generics::image::EndingShape as GenericEndingShape;
-use style::values::generics::image::GradientItem as GenericGradientItem;
 use style::values::generics::image::{Circle, ColorStop, Ellipse, ShapeExtent};
 use style::values::specified::position::{X, Y};
 use webrender_api::{ExtendMode, Gradient, GradientBuilder, GradientStop, RadialGradient};
@@ -92,11 +88,11 @@ fn convert_gradient_stops(
     let mut stop_items = gradient_items
         .iter()
         .filter_map(|item| match *item {
-            GenericGradientItem::SimpleColorStop(color) => Some(ColorStop {
+            GradientItem::SimpleColorStop(color) => Some(ColorStop {
                 color,
                 position: None,
             }),
-            GenericGradientItem::ComplexColorStop { color, position } => Some(ColorStop {
+            GradientItem::ComplexColorStop { color, position } => Some(ColorStop {
                 color,
                 position: Some(position),
             }),
@@ -301,17 +297,15 @@ pub fn radial(
         center.vertical.to_used_value(size.height),
     );
     let radius = match shape {
-        GenericEndingShape::Circle(Circle::Radius(length)) => {
+        EndingShape::Circle(Circle::Radius(length)) => {
             let length = Au::from(length);
             Size2D::new(length, length)
         },
-        GenericEndingShape::Circle(Circle::Extent(extent)) => {
-            circle_size_keyword(extent, &size, &center)
-        },
-        GenericEndingShape::Ellipse(Ellipse::Radii(x, y)) => {
+        EndingShape::Circle(Circle::Extent(extent)) => circle_size_keyword(extent, &size, &center),
+        EndingShape::Ellipse(Ellipse::Radii(x, y)) => {
             Size2D::new(x.to_used_value(size.width), y.to_used_value(size.height))
         },
-        GenericEndingShape::Ellipse(Ellipse::Extent(extent)) => {
+        EndingShape::Ellipse(Ellipse::Extent(extent)) => {
             ellipse_size_keyword(extent, &size, &center)
         },
     };