Auto merge of #15287 - hiikezoe:css-animation, r=heycam

Counter part of bug 1328787 - Stylo: Convert Servo's animation keyframes and store them into Gecko's keyframes

<!-- Please describe your changes on the following line: -->
Reviewed by @heycam, An exception is auto-generated bindgen stuff, I did not include it in patches on bugzilla.  The bindgen diff included in this PR was generated with  b5c94bad37.  It might be bit-rotted.

---
<!-- Thank you for contributing to Servo! Please replace each `[ ]` by `[X]` when the step is complete, and replace `__` with appropriate data: -->
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [ ] These changes fix #__ (github issue number if applicable).

<!-- Either: -->
- [ ] There are tests for these changes OR
- [X] These changes do not require tests because gecko has test cases.

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components/style/properties/gecko.mako.rs

@@ -51,11 +51,14 @@ use gecko::values::GeckoStyleCoordConvertible;
 use gecko::values::round_border_to_device_pixels;
 use logical_geometry::WritingMode;
 use properties::longhands;
+use properties::{DeclaredValue, Importance, LonghandId};
+use properties::{PropertyDeclaration, PropertyDeclarationBlock, PropertyDeclarationId};
 use std::fmt::{self, Debug};
 use std::mem::{transmute, zeroed};
 use std::ptr;
 use std::sync::Arc;
 use std::cmp;
+use values::computed::ToComputedValue;
 
 pub mod style_structs {
     % for style_struct in data.style_structs:
@@ -154,6 +157,28 @@ impl ComputedValues {
     // FIXME(bholley): Implement this properly.
     #[inline]
     pub fn is_multicol(&self) -> bool { false }
+
+    pub fn to_declaration_block(&self, property: PropertyDeclarationId) -> PropertyDeclarationBlock {
+        match property {
+            % for prop in data.longhands:
+                % if prop.animatable:
+                    PropertyDeclarationId::Longhand(LonghandId::${prop.camel_case}) => {
+                        PropertyDeclarationBlock {
+                            declarations: vec![
+                                (PropertyDeclaration::${prop.camel_case}(DeclaredValue::Value(
+                                    longhands::${prop.ident}::SpecifiedValue::from_computed_value(
+                                      &self.get_${prop.style_struct.ident.strip("_")}().clone_${prop.ident}()))),
+                                 Importance::Normal)
+                            ],
+                            important_count: 0
+                        }
+                    },
+                % endif
+            % endfor
+            PropertyDeclarationId::Custom(_name) => unimplemented!(),
+            _ => unimplemented!()
+        }
+    }
 }
 
 <%def name="declare_style_struct(style_struct)">

components/style/properties/helpers.mako.rs

@@ -665,3 +665,20 @@
         }
     % endif
 </%def>
+
+<%def name="alias_to_nscsspropertyid(alias)">
+    <%
+        if alias == "word-wrap":
+            return "nsCSSPropertyID_eCSSPropertyAlias_WordWrap"
+        return "nsCSSPropertyID::eCSSPropertyAlias_%s" % to_camel_case(alias)
+    %>
+</%def>
+
+<%def name="to_nscsspropertyid(ident)">
+    <%
+        if ident == "float":
+            ident = "float_"
+        return "nsCSSPropertyID::eCSSProperty_%s" % ident
+    %>
+</%def>
+

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

@@ -2,9 +2,12 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+<%namespace name="helpers" file="/helpers.mako.rs" />
+
 use app_units::Au;
 use cssparser::{Color as CSSParserColor, Parser, RGBA};
 use euclid::{Point2D, Size2D};
+#[cfg(feature = "gecko")] use gecko_bindings::structs::nsCSSPropertyID;
 use properties::{DeclaredValue, PropertyDeclaration};
 use properties::longhands;
 use properties::longhands::background_position_x::computed_value::T as BackgroundPositionX;
@@ -19,6 +22,7 @@ use properties::longhands::box_shadow::single_value::computed_value::T as BoxSha
 use properties::longhands::vertical_align::computed_value::T as VerticalAlign;
 use properties::longhands::visibility::computed_value::T as Visibility;
 use properties::longhands::z_index::computed_value::T as ZIndex;
+#[cfg(feature = "gecko")] use properties::{PropertyDeclarationId, LonghandId};
 use std::cmp;
 use std::fmt;
 use style_traits::ToCss;
@@ -101,6 +105,40 @@ impl ToCss for TransitionProperty {
     }
 }
 
+/// Convert to nsCSSPropertyID.
+#[cfg(feature = "gecko")]
+#[allow(non_upper_case_globals)]
+impl From<TransitionProperty> for nsCSSPropertyID {
+    fn from(transition_property: TransitionProperty) -> nsCSSPropertyID {
+        match transition_property {
+            % for prop in data.longhands:
+                % if prop.animatable:
+                    TransitionProperty::${prop.camel_case}
+                        => ${helpers.to_nscsspropertyid(prop.ident)},
+                % endif
+            % endfor
+            TransitionProperty::All => nsCSSPropertyID::eCSSPropertyExtra_all_properties,
+        }
+    }
+}
+
+/// Convert to PropertyDeclarationId.
+#[cfg(feature = "gecko")]
+#[allow(non_upper_case_globals)]
+impl<'a> From<TransitionProperty> for PropertyDeclarationId<'a> {
+    fn from(transition_property: TransitionProperty) -> PropertyDeclarationId<'a> {
+        match transition_property {
+            % for prop in data.longhands:
+                % if prop.animatable:
+                    TransitionProperty::${prop.camel_case}
+                        => PropertyDeclarationId::Longhand(LonghandId::${prop.camel_case}),
+                % endif
+            % endfor
+            TransitionProperty::All => panic!(),
+        }
+    }
+}
+
 /// An animated property interpolation between two computed values for that
 /// property.
 #[derive(Clone, Debug, PartialEq)]

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

@@ -830,7 +830,7 @@ ${helpers.single_keyword("overflow-x", "visible hidden scroll auto",
                           animatable="False",
                           extra_prefixes="moz webkit"
                           spec="https://drafts.csswg.org/css-animations/#propdef-animation-timing-function",
-                          allowed_in_keyframe_block="False">
+                          allowed_in_keyframe_block="True">
     pub use properties::longhands::transition_timing_function::single_value::computed_value;
     pub use properties::longhands::transition_timing_function::single_value::get_initial_value;
     pub use properties::longhands::transition_timing_function::single_value::get_initial_specified_value;

components/style/properties/properties.mako.rs

@@ -737,16 +737,6 @@ enum StaticId {
     Shorthand(ShorthandId),
 }
 include!(concat!(env!("OUT_DIR"), "/static_ids.rs"));
-<%
-    def alias_to_nscsspropertyid(alias):
-        if alias == "word-wrap":
-            return "nsCSSPropertyID_eCSSPropertyAlias_WordWrap"
-        return "nsCSSPropertyID::eCSSPropertyAlias_%s" % to_camel_case(alias)
-    def to_nscsspropertyid(ident):
-        if ident == "float":
-            ident = "float_"
-        return "nsCSSPropertyID::eCSSProperty_%s" % ident
-%>
 impl PropertyId {
     /// Returns a given property from the string `s`.
     ///
@@ -771,21 +761,21 @@ impl PropertyId {
         use gecko_bindings::structs::*;
         match id {
             % for property in data.longhands:
-                ${to_nscsspropertyid(property.ident)} => {
+                ${helpers.to_nscsspropertyid(property.ident)} => {
                     Ok(PropertyId::Longhand(LonghandId::${property.camel_case}))
                 }
                 % for alias in property.alias:
-                    ${alias_to_nscsspropertyid(alias)} => {
+                    ${helpers.alias_to_nscsspropertyid(alias)} => {
                         Ok(PropertyId::Longhand(LonghandId::${property.camel_case}))
                     }
                 % endfor
             % endfor
             % for property in data.shorthands:
-                ${to_nscsspropertyid(property.ident)} => {
+                ${helpers.to_nscsspropertyid(property.ident)} => {
                     Ok(PropertyId::Shorthand(ShorthandId::${property.camel_case}))
                 }
                 % for alias in property.alias:
-                    ${alias_to_nscsspropertyid(alias)} => {
+                    ${helpers.alias_to_nscsspropertyid(alias)} => {
                         Ok(PropertyId::Shorthand(ShorthandId::${property.camel_case}))
                     }
                 % endfor
@@ -804,14 +794,14 @@ impl PropertyId {
             PropertyId::Longhand(id) => match id {
                 % for property in data.longhands:
                     LonghandId::${property.camel_case} => {
-                        Ok(${to_nscsspropertyid(property.ident)})
+                        Ok(${helpers.to_nscsspropertyid(property.ident)})
                     }
                 % endfor
             },
             PropertyId::Shorthand(id) => match id {
                 % for property in data.shorthands:
                     ShorthandId::${property.camel_case} => {
-                        Ok(${to_nscsspropertyid(property.ident)})
+                        Ok(${helpers.to_nscsspropertyid(property.ident)})
                     }
                 % endfor
             },
@@ -921,7 +911,7 @@ impl ToCss for PropertyDeclaration {
                 pref_ident = "float_"
         %>
         if structs::root::mozilla::SERVO_PREF_ENABLED_${pref_ident} {
-            let id = structs::${to_nscsspropertyid(property.ident)};
+            let id = structs::${helpers.to_nscsspropertyid(property.ident)};
             let enabled = unsafe { bindings::Gecko_PropertyId_IsPrefEnabled(id) };
             if !enabled {
                 return PropertyDeclarationParseResult::ExperimentalProperty