From 34556f7769ddd7e9a215f44b1eb65e13881531e0 Mon Sep 17 00:00:00 2001
From: Brian Birtles <birtles@gmail.com>
Date: Mon, 5 Jun 2017 12:03:38 +0900
Subject: [PATCH] Add FFI for getting the zero value of an animation value

---
 components/style/gecko/generated/bindings.rs |  5 +++++
 ports/geckolib/glue.rs                       | 13 +++++++++++++
 2 files changed, 18 insertions(+)

diff --git a/components/style/gecko/generated/bindings.rs b/components/style/gecko/generated/bindings.rs
index f08d4b50f2d..015ee090d3b 100644
--- a/components/style/gecko/generated/bindings.rs
+++ b/components/style/gecko/generated/bindings.rs
@@ -2185,6 +2185,11 @@ extern "C" {
                                                     RawServoAnimationValueBorrowed)
      -> bool;
 }
+extern "C" {
+    pub fn Servo_AnimationValues_GetZeroValue(value_to_match:
+                                                  RawServoAnimationValueBorrowed)
+     -> RawServoAnimationValueStrong;
+}
 extern "C" {
     pub fn Servo_AnimationValues_ComputeDistance(from:
                                                      RawServoAnimationValueBorrowed,
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 4ef66b422c1..6094a8cdd57 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -313,6 +313,19 @@ pub extern "C" fn Servo_AnimationValues_IsInterpolable(from: RawServoAnimationVa
     from_value.interpolate(to_value, 0.5).is_ok()
 }
 
+#[no_mangle]
+pub extern "C" fn Servo_AnimationValues_GetZeroValue(
+    value_to_match: RawServoAnimationValueBorrowed)
+    -> RawServoAnimationValueStrong
+{
+    let value_to_match = AnimationValue::as_arc(&value_to_match);
+    if let Some(zero_value) = value_to_match.get_zero_value() {
+        Arc::new(zero_value).into_strong()
+    } else {
+        RawServoAnimationValueStrong::null()
+    }
+}
+
 #[no_mangle]
 pub extern "C" fn Servo_AnimationValues_ComputeDistance(from: RawServoAnimationValueBorrowed,
                                                         to: RawServoAnimationValueBorrowed)