Auto merge of #16693 - nox:touch-action, r=emilio

Implement touch-action in stylo (fixes #16372)

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components/style/properties/gecko.mako.rs

@@ -1771,7 +1771,7 @@ fn static_assert() {
                           scroll-snap-points-x scroll-snap-points-y transform
                           scroll-snap-type-y scroll-snap-coordinate
                           perspective-origin transform-origin -moz-binding will-change
-                          shape-outside contain""" %>
+                          shape-outside contain touch-action""" %>
 <%self:impl_trait style_struct_name="Box" skip_longhands="${skip_box_longhands}">
 
     // We manually-implement the |display| property until we get general
@@ -2488,6 +2488,12 @@ fn static_assert() {
     }
 
     ${impl_simple_copy("contain", "mContain")}
+
+    pub fn set_touch_action(&mut self, v: longhands::touch_action::computed_value::T) {
+        self.gecko.mTouchAction = v.bits();
+    }
+
+    ${impl_simple_copy("touch_action", "mTouchAction")}
 </%self:impl_trait>
 
 <%def name="simple_image_array_property(name, shorthand, field_name)">

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

@@ -2514,3 +2514,82 @@ ${helpers.predefined_type("shape-outside", "basic_shape::ShapeWithShapeBox",
                           products="gecko", boxed="True",
                           animation_value_type="none",
                           spec="https://drafts.csswg.org/css-shapes/#shape-outside-property")}
+
+<%helpers:longhand name="touch-action"
+                   products="gecko"
+                   animation_value_type="none"
+                   disable_when_testing="True"
+                   spec="https://compat.spec.whatwg.org/#touch-action">
+    use gecko_bindings::structs;
+    use std::fmt;
+    use style_traits::ToCss;
+    use values::HasViewportPercentage;
+    use values::computed::ComputedValueAsSpecified;
+
+    impl ComputedValueAsSpecified for SpecifiedValue {}
+    no_viewport_percentage!(SpecifiedValue);
+
+    pub mod computed_value {
+        pub use super::SpecifiedValue as T;
+    }
+
+    bitflags! {
+        /// These constants match Gecko's `NS_STYLE_TOUCH_ACTION_*` constants.
+        pub flags SpecifiedValue: u8 {
+            const TOUCH_ACTION_NONE = structs::NS_STYLE_TOUCH_ACTION_NONE as u8,
+            const TOUCH_ACTION_AUTO = structs::NS_STYLE_TOUCH_ACTION_AUTO as u8,
+            const TOUCH_ACTION_PAN_X = structs::NS_STYLE_TOUCH_ACTION_PAN_X as u8,
+            const TOUCH_ACTION_PAN_Y = structs::NS_STYLE_TOUCH_ACTION_PAN_Y as u8,
+            const TOUCH_ACTION_MANIPULATION = structs::NS_STYLE_TOUCH_ACTION_MANIPULATION as u8,
+        }
+    }
+
+    impl ToCss for SpecifiedValue {
+        fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
+            match *self {
+                TOUCH_ACTION_NONE => dest.write_str("none"),
+                TOUCH_ACTION_AUTO => dest.write_str("auto"),
+                TOUCH_ACTION_MANIPULATION => dest.write_str("manipulation"),
+                _ if self.contains(TOUCH_ACTION_PAN_X | TOUCH_ACTION_PAN_Y) => {
+                    dest.write_str("pan-x pan-y")
+                },
+                _ if self.contains(TOUCH_ACTION_PAN_X) => {
+                    dest.write_str("pan-x")
+                },
+                _ if self.contains(TOUCH_ACTION_PAN_Y) => {
+                    dest.write_str("pan-y")
+                },
+                _ => panic!("invalid touch-action value"),
+            }
+        }
+    }
+
+    #[inline]
+    pub fn get_initial_value() -> computed_value::T {
+        TOUCH_ACTION_AUTO
+    }
+
+    pub fn parse(_context: &ParserContext, input: &mut Parser) -> Result<SpecifiedValue, ()> {
+        let ident = input.expect_ident()?;
+        match_ignore_ascii_case! { &ident,
+            "auto" => Ok(TOUCH_ACTION_AUTO),
+            "none" => Ok(TOUCH_ACTION_NONE),
+            "manipulation" => Ok(TOUCH_ACTION_MANIPULATION),
+            "pan-x" => {
+                if input.try(|i| i.expect_ident_matching("pan-y")).is_ok() {
+                    Ok(TOUCH_ACTION_PAN_X | TOUCH_ACTION_PAN_Y)
+                } else {
+                    Ok(TOUCH_ACTION_PAN_X)
+                }
+            },
+            "pan-y" => {
+                if input.try(|i| i.expect_ident_matching("pan-x")).is_ok() {
+                    Ok(TOUCH_ACTION_PAN_X | TOUCH_ACTION_PAN_Y)
+                } else {
+                    Ok(TOUCH_ACTION_PAN_Y)
+                }
+            },
+            _ => Err(()),
+        }
+    }
+</%helpers:longhand>