From 95b272d9aaaa6c9b7469b168aebf5d97c43bc806 Mon Sep 17 00:00:00 2001
From: Mantaroh Yoshinaga <mantaroh@gmail.com>
Date: Wed, 14 Jun 2017 11:03:53 +0900
Subject: [PATCH] Return zero when computing distance of Option with both value
 is none.

---
 components/style/properties/helpers/animated_properties.mako.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/components/style/properties/helpers/animated_properties.mako.rs b/components/style/properties/helpers/animated_properties.mako.rs
index a03d55070aa..857c0b10491 100644
--- a/components/style/properties/helpers/animated_properties.mako.rs
+++ b/components/style/properties/helpers/animated_properties.mako.rs
@@ -853,6 +853,7 @@ impl <T> Animatable for Option<T>
             (&Some(ref this), &Some(ref other)) => {
                 this.compute_squared_distance(other)
             },
+            (&None, &None) => Ok(0.0),
             _ => Err(()),
         }
     }