Auto merge of #15175 - BorisChiou:animation/interpolate_and_cascade, r=heycam

Interpolate servo animation values and add them to the cascade

These are the servo-side changes for [bug 1317209](https://bugzilla.mozilla.org/show_bug.cgi?id=1317209). @Manishearth, @emilio, and @heycam have already reviewed them there. Please merge these patches until the gecko-side changes for [bug 1317209](https://bugzilla.mozilla.org/show_bug.cgi?id=1317209) is landed.

---
- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix [bug 1317209](https://bugzilla.mozilla.org/show_bug.cgi?id=1317209).
- [X] These changes do not require tests because there are existing tests for this in mozilla-central

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components/style/gecko_bindings/bindings.rs

@@ -3,11 +3,13 @@
 pub use nsstring::{nsACString, nsAString};
 type nsACString_internal = nsACString;
 type nsAString_internal = nsAString;
+use gecko_bindings::structs::EffectCompositor_CascadeLevel;
 use gecko_bindings::structs::RawGeckoDocument;
 use gecko_bindings::structs::RawGeckoElement;
 use gecko_bindings::structs::RawGeckoNode;
 use gecko_bindings::structs::RawGeckoAnimationValueList;
 use gecko_bindings::structs::RawServoAnimationValue;
+use gecko_bindings::structs::RawServoAnimationValueBorrowedList;
 use gecko_bindings::structs::RawGeckoPresContext;
 use gecko_bindings::structs::RawGeckoPresContextOwned;
 use gecko_bindings::structs::ThreadSafeURIHolder;
@@ -224,6 +226,8 @@ pub type RawGeckoAnimationValueListBorrowed<'a> = &'a RawGeckoAnimationValueList
 pub type RawGeckoAnimationValueListBorrowedOrNull<'a> = Option<&'a RawGeckoAnimationValueList>;
 pub type RawGeckoAnimationValueListBorrowedMut<'a> = &'a mut RawGeckoAnimationValueList;
 pub type RawGeckoAnimationValueListBorrowedMutOrNull<'a> = Option<&'a mut RawGeckoAnimationValueList>;
+pub type RawServoAnimationValueBorrowedListBorrowed<'a> = &'a RawServoAnimationValueBorrowedList;
+pub type RawServoAnimationValueBorrowedListBorrowedOrNull<'a> = Option<&'a RawServoAnimationValueBorrowedList>;
 
 extern "C" {
     pub fn Gecko_EnsureTArrayCapacity(aArray: *mut ::std::os::raw::c_void,
@@ -498,6 +502,12 @@ extern "C" {
     pub fn Gecko_GetServoDeclarationBlock(element: RawGeckoElementBorrowed)
      -> RawServoDeclarationBlockStrongBorrowedOrNull;
 }
+extern "C" {
+    pub fn Gecko_GetAnimationRule(element: RawGeckoElementBorrowed,
+                                  aAtom: *mut nsIAtom,
+                                  aCascadeLevel: EffectCompositor_CascadeLevel)
+     -> RawServoDeclarationBlockStrong;
+}
 extern "C" {
     pub fn Gecko_Atomize(aString: *const ::std::os::raw::c_char, aLength: u32)
      -> *mut nsIAtom;
@@ -1217,6 +1227,16 @@ extern "C" {
                                                  ServoComputedValuesBorrowed)
      -> ServoComputedValuesStrong;
 }
+extern "C" {
+    pub fn Servo_AnimationValues_Interpolate(from: RawServoAnimationValueBorrowed,
+                                             to: RawServoAnimationValueBorrowed,
+                                             progress: f64)
+     -> RawServoAnimationValueStrong;
+}
+extern "C" {
+    pub fn Servo_AnimationValues_Uncompute(value: RawServoAnimationValueBorrowedListBorrowed)
+     -> RawServoDeclarationBlockStrong;
+}
 extern "C" {
     pub fn Servo_AnimationValues_Populate(arg1:
                                               RawGeckoAnimationValueListBorrowedMut,

components/style/gecko_bindings/structs_debug.rs

@@ -5273,6 +5273,12 @@ pub mod root {
         impl Clone for StyleComplexColor {
             fn clone(&self) -> Self { *self }
         }
+        #[repr(u32)]
+        #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+        pub enum EffectCompositor_CascadeLevel {
+            Animations = 0,
+            Transitions = 1,
+        }
         #[repr(C)]
         #[derive(Debug)]
         pub struct PropertyStyleAnimationValuePair {
@@ -17953,6 +17959,10 @@ pub mod root {
     pub type RawGeckoPresContextBorrowedMut = *mut root::RawGeckoPresContext;
     pub type RawGeckoAnimationValueListBorrowedMut =
         *mut root::RawGeckoAnimationValueList;
+    pub type RawServoAnimationValueBorrowedList =
+        root::nsTArray<*const root::RawServoAnimationValue>;
+    pub type RawServoAnimationValueBorrowedListBorrowed =
+        *const root::RawServoAnimationValueBorrowedList;
     #[repr(u32)]
     #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
     pub enum nsCSSTokenSerializationType {

components/style/gecko_bindings/structs_release.rs

@@ -5191,6 +5191,12 @@ pub mod root {
         impl Clone for StyleComplexColor {
             fn clone(&self) -> Self { *self }
         }
+        #[repr(u32)]
+        #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
+        pub enum EffectCompositor_CascadeLevel {
+            Animations = 0,
+            Transitions = 1,
+        }
         #[repr(C)]
         #[derive(Debug)]
         pub struct PropertyStyleAnimationValuePair {
@@ -17726,6 +17732,10 @@ pub mod root {
     pub type RawGeckoPresContextBorrowedMut = *mut root::RawGeckoPresContext;
     pub type RawGeckoAnimationValueListBorrowedMut =
         *mut root::RawGeckoAnimationValueList;
+    pub type RawServoAnimationValueBorrowedList =
+        root::nsTArray<*const root::RawServoAnimationValue>;
+    pub type RawServoAnimationValueBorrowedListBorrowed =
+        *const root::RawServoAnimationValueBorrowedList;
     #[repr(u32)]
     #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
     pub enum nsCSSTokenSerializationType {