Auto merge of #14370 - thiagopnts:master, r=Wafflespeanut

use Either type for UrlOrNone

Use the Either type for UrlOrNone

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes fix #14298 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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components/style/properties/gecko.mako.rs

@@ -1089,10 +1089,10 @@ fn static_assert() {
 
     #[allow(non_snake_case)]
     pub fn set__moz_binding(&mut self, v: longhands::_moz_binding::computed_value::T) {
-        use properties::longhands::_moz_binding::computed_value::T as BindingValue;
+        use values::Either;
         match v {
-            BindingValue::None => debug_assert!(self.gecko.mBinding.mRawPtr.is_null()),
-            BindingValue::Url(ref url) => {
+            Either::Second(_none) => debug_assert!(self.gecko.mBinding.mRawPtr.is_null()),
+            Either::First(ref url) => {
                 let extra_data = url.extra_data();
                 let (ptr, len) = url.as_slice_components();
                 unsafe {
@@ -1617,14 +1617,14 @@ fn static_assert() {
                   skip_additionals="*">
 
     pub fn set_list_style_image(&mut self, image: longhands::list_style_image::computed_value::T) {
-        use values::computed::UrlOrNone;
+        use values::Either;
         match image {
-            UrlOrNone::None => {
+            Either::Second(_none) => {
                 unsafe {
                     Gecko_SetListStyleImageNone(&mut self.gecko);
                 }
             }
-            UrlOrNone::Url(ref url) => {
+            Either::First(ref url) => {
                 let (ptr, len) = url.as_slice_components();
                 let extra_data = url.extra_data();
                 unsafe {

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

@@ -1551,7 +1551,7 @@ ${helpers.single_keyword("-moz-appearance",
                          animatable=False)}
 
 // Non-standard: https://developer.mozilla.org/en-US/docs/Web/CSS/-moz-binding
-${helpers.predefined_type("-moz-binding", "UrlOrNone", "computed_value::T::None",
+${helpers.predefined_type("-moz-binding", "UrlOrNone", "Either::Second(None_)",
                           products="gecko",
                           animatable="False",
                           disable_when_testing="True")}

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

@@ -26,7 +26,7 @@ ${helpers.single_keyword("list-style-type", """
     gecko_constant_prefix="NS_STYLE_LIST_STYLE",
     animatable=False)}
 
-${helpers.predefined_type("list-style-image", "UrlOrNone", "computed_value::T::None",
+${helpers.predefined_type("list-style-image", "UrlOrNone", "Either::Second(None_)",
                           animatable="False")}
 
 <%helpers:longhand name="quotes" animatable="False">

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

@@ -7,6 +7,7 @@
 <%helpers:shorthand name="list-style"
                     sub_properties="list-style-image list-style-position list-style-type">
     use properties::longhands::{list_style_image, list_style_position, list_style_type};
+    use values::{Either, None_};
 
     pub fn parse_value(context: &ParserContext, input: &mut Parser) -> Result<Longhands, ()> {
         // `none` is ambiguous until we've finished parsing the shorthands, so we count the number
@@ -56,7 +57,7 @@
             (true, 2, None, None) => {
                 Ok(Longhands {
                     list_style_position: position,
-                    list_style_image: Some(list_style_image::SpecifiedValue::None),
+                    list_style_image: Some(Either::Second(None_)),
                     list_style_type: Some(list_style_type::SpecifiedValue::none),
                 })
             }
@@ -70,14 +71,14 @@
             (true, 1, Some(list_style_type), None) => {
                 Ok(Longhands {
                     list_style_position: position,
-                    list_style_image: Some(list_style_image::SpecifiedValue::None),
+                    list_style_image: Some(Either::Second(None_)),
                     list_style_type: Some(list_style_type),
                 })
             }
             (true, 1, None, None) => {
                 Ok(Longhands {
                     list_style_position: position,
-                    list_style_image: Some(list_style_image::SpecifiedValue::None),
+                    list_style_image: Some(Either::Second(None_)),
                     list_style_type: Some(list_style_type::SpecifiedValue::none),
                 })
             }