servo: Merge #16055 - stylo: Bug 1343153 - Use servo css-parser for ParseEasing (from BorisChiou:stylo/animation/parse_easing); r=emilio

These patches fix [Bug 1343153](https://bugzilla.mozilla.org/show_bug.cgi?id=1343153).

---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix Bug 1343153
- [X] These changes do not require tests because gecko has enough test cases for web animations.

Source-Repo: https://github.com/servo/servo
Source-Revision: 5a656cfa54c7c125b309721f587d591d515999c2

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : 05696cc5a76eecf0ace9e8b8f137c067014ba070

servo/components/style/build_gecko.rs

@@ -691,6 +691,7 @@ mod bindings {
         ];
         let servo_borrow_types = [
             "nsCSSValue",
+            "nsTimingFunction",
             "RawGeckoAnimationValueList",
             "RawGeckoKeyframeList",
             "RawGeckoComputedKeyframeValuesList",

servo/components/style/gecko_bindings/bindings.rs

@@ -263,6 +263,10 @@ pub type nsCSSValueBorrowed<'a> = &'a nsCSSValue;
 pub type nsCSSValueBorrowedOrNull<'a> = Option<&'a nsCSSValue>;
 pub type nsCSSValueBorrowedMut<'a> = &'a mut nsCSSValue;
 pub type nsCSSValueBorrowedMutOrNull<'a> = Option<&'a mut nsCSSValue>;
+pub type nsTimingFunctionBorrowed<'a> = &'a nsTimingFunction;
+pub type nsTimingFunctionBorrowedOrNull<'a> = Option<&'a nsTimingFunction>;
+pub type nsTimingFunctionBorrowedMut<'a> = &'a mut nsTimingFunction;
+pub type nsTimingFunctionBorrowedMutOrNull<'a> = Option<&'a mut nsTimingFunction>;
 pub type RawGeckoAnimationValueListBorrowed<'a> = &'a RawGeckoAnimationValueList;
 pub type RawGeckoAnimationValueListBorrowedOrNull<'a> = Option<&'a RawGeckoAnimationValueList>;
 pub type RawGeckoAnimationValueListBorrowedMut<'a> = &'a mut RawGeckoAnimationValueList;
@@ -1390,7 +1394,7 @@ extern "C" {
     pub fn Servo_StyleSet_FillKeyframesForName(set: RawServoStyleSetBorrowed,
                                                property: *const nsACString,
                                                timing_function:
-                                                   *const nsTimingFunction,
+                                                   nsTimingFunctionBorrowed,
                                                computed_values:
                                                    ServoComputedValuesBorrowed,
                                                keyframe_list:
@@ -1487,6 +1491,12 @@ extern "C" {
                                data: *const GeckoParserExtraData)
      -> RawServoDeclarationBlockStrong;
 }
+extern "C" {
+    pub fn Servo_ParseEasing(easing: *const nsAString,
+                             base: *const nsACString,
+                             data: *const GeckoParserExtraData,
+                             output: nsTimingFunctionBorrowedMut) -> bool;
+}
 extern "C" {
     pub fn Servo_GetComputedKeyframeValues(keyframes:
                                                RawGeckoKeyframeListBorrowed,

servo/ports/geckolib/glue.rs

@@ -48,6 +48,8 @@ use style::gecko_bindings::bindings::RawServoAnimationValueStrong;
 use style::gecko_bindings::bindings::RawServoImportRuleBorrowed;
 use style::gecko_bindings::bindings::ServoComputedValuesBorrowedOrNull;
 use style::gecko_bindings::bindings::nsTArrayBorrowed_uintptr_t;
+use style::gecko_bindings::bindings::nsTimingFunctionBorrowed;
+use style::gecko_bindings::bindings::nsTimingFunctionBorrowedMut;
 use style::gecko_bindings::structs;
 use style::gecko_bindings::structs::{SheetParsingMode, nsIAtom, nsCSSPropertyID};
 use style::gecko_bindings::structs::{ThreadSafePrincipalHolder, ThreadSafeURIHolder};
@@ -56,7 +58,6 @@ use style::gecko_bindings::structs::Loader;
 use style::gecko_bindings::structs::RawGeckoPresContextOwned;
 use style::gecko_bindings::structs::ServoStyleSheet;
 use style::gecko_bindings::structs::nsCSSValueSharedList;
-use style::gecko_bindings::structs::nsTimingFunction;
 use style::gecko_bindings::structs::nsresult;
 use style::gecko_bindings::sugar::ownership::{FFIArcHelpers, HasArcFFI, HasBoxFFI};
 use style::gecko_bindings::sugar::ownership::{HasSimpleFFI, Strong};
@@ -790,6 +791,27 @@ pub extern "C" fn Servo_ParseProperty(property: *const nsACString, value: *const
     }
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_ParseEasing(easing: *const nsAString,
+                                    base: *const nsACString,
+                                    data: *const structs::GeckoParserExtraData,
+                                    output: nsTimingFunctionBorrowedMut)
+                                    -> bool {
+    use style::properties::longhands::transition_timing_function;
+
+    make_context!((base, data) => (base_url, extra_data));
+    let reporter = StdoutErrorReporter;
+    let context = ParserContext::new_with_extra_data(Origin::Author, &base_url, &reporter, extra_data);
+    let easing = unsafe { (*easing).to_string() };
+    match transition_timing_function::single_value::parse(&context, &mut Parser::new(&easing)) {
+        Ok(parsed_easing) => {
+            *output = parsed_easing.into();
+            true
+        },
+        Err(_) => false
+    }
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_ParseStyleAttribute(data: *const nsACString,
                                             base: *const nsACString,
@@ -1617,7 +1639,7 @@ pub extern "C" fn Servo_AssertTreeIsClean(root: RawGeckoElementBorrowed) {
 #[no_mangle]
 pub extern "C" fn Servo_StyleSet_FillKeyframesForName(raw_data: RawServoStyleSetBorrowed,
                                                       name: *const nsACString,
-                                                      timing_function: *const nsTimingFunction,
+                                                      timing_function: nsTimingFunctionBorrowed,
                                                       style: ServoComputedValuesBorrowed,
                                                       keyframes: RawGeckoKeyframeListBorrowedMut) -> bool {
     use style::gecko_bindings::structs::Keyframe;
@@ -1626,7 +1648,6 @@ pub extern "C" fn Servo_StyleSet_FillKeyframesForName(raw_data: RawServoStyleSet
 
     let data = PerDocumentStyleData::from_ffi(raw_data).borrow();
     let name = unsafe { Atom::from(name.as_ref().unwrap().as_str_unchecked()) };
-    let style_timing_function = unsafe { timing_function.as_ref().unwrap() };
     let style = ComputedValues::as_arc(&style);
 
     if let Some(ref animation) = data.stylist.animations().get(&name) {
@@ -1637,13 +1658,13 @@ pub extern "C" fn Servo_StyleSet_FillKeyframesForName(raw_data: RawServoStyleSet
           let timing_function = if let Some(val) = step.get_animation_timing_function(&guard) {
               val.into()
           } else {
-              *style_timing_function
+              *timing_function
           };
 
           let keyframe = unsafe {
-                Gecko_AnimationAppendKeyframe(keyframes,
-                                              step.start_percentage.0 as f32,
-                                              &timing_function)
+              Gecko_AnimationAppendKeyframe(keyframes,
+                                            step.start_percentage.0 as f32,
+                                            &timing_function)
           };
 
           fn add_computed_property_value(keyframe: *mut Keyframe,