Factor out restyle_kind_for_animation.

1 files changed, 24 insertions, 12 deletions

diff --git a/components/style/data.rs b/components/style/data.rs
index 2478f9761c3..5d2771121a1 100644
--- a/components/style/data.rs
+++ b/components/style/data.rs
@@ -278,25 +278,17 @@ impl ElementData {
     pub fn restyle_kind(&self,
                         shared_context: &SharedStyleContext)
                         -> RestyleKind {
+        if shared_context.traversal_flags.for_animation_only() {
+            return self.restyle_kind_for_animation(shared_context);
+        }
+
         debug_assert!(!self.has_styles() || self.has_invalidations(),
                       "Should've stopped earlier");
         if !self.has_styles() {
-            debug_assert!(!shared_context.traversal_flags.for_animation_only(),
-                          "Unstyled element shouldn't be traversed during \
-                           animation-only traversal");
             return RestyleKind::MatchAndCascade;
         }
 
         let hint = self.restyle.hint;
-        if shared_context.traversal_flags.for_animation_only() {
-            // return either CascadeWithReplacements or CascadeOnly in case of
-            // animation-only restyle.
-            if hint.has_animation_hint() {
-                return RestyleKind::CascadeWithReplacements(hint & RestyleHint::for_animations());
-            }
-            return RestyleKind::CascadeOnly;
-        }
-
         if hint.match_self() {
             return RestyleKind::MatchAndCascade;
         }
@@ -312,6 +304,26 @@ impl ElementData {
         return RestyleKind::CascadeOnly;
     }
 
+    /// Returns the kind of restyling for animation-only restyle.
+    pub fn restyle_kind_for_animation(&self,
+                                      shared_context: &SharedStyleContext)
+                                      -> RestyleKind {
+        debug_assert!(shared_context.traversal_flags.for_animation_only());
+        debug_assert!(self.has_styles(),
+                      "Unstyled element shouldn't be traversed during \
+                       animation-only traversal");
+
+        // return either CascadeWithReplacements or CascadeOnly in case of
+        // animation-only restyle. I.e. animation-only restyle never does
+        // selector matching.
+        let hint = self.restyle.hint;
+        if hint.has_animation_hint() {
+            return RestyleKind::CascadeWithReplacements(hint & RestyleHint::for_animations());
+        }
+        return RestyleKind::CascadeOnly;
+
+    }
+
     /// Return true if important rules are different.
     /// We use this to make sure the cascade of off-main thread animations is correct.
     /// Note: Ignore custom properties for now because we only support opacity and transform