diff --git a/components/style/stylesheet_set.rs b/components/style/stylesheet_set.rs
index 8548ac53f01..0d8d032402f 100644
--- a/components/style/stylesheet_set.rs
+++ b/components/style/stylesheet_set.rs
@@ -180,14 +180,12 @@ where
             .any(|(d, _)| d.dirty)
     }
 
-    /// Flush the current set, unmarking it as dirty, and returns an iterator
-    /// over the new stylesheet list.
-    ///
-    /// Returns true if any elements were invalidated.
+    /// Flush the current set, unmarking it as dirty, and returns the damaged
+    /// origins, and whether any elements were invalidated.
     pub fn flush<E>(
         &mut self,
         document_element: Option<E>,
-    ) -> (StylesheetIterator<S>, OriginSet, bool)
+    ) -> (OriginSet, bool)
     where
         E: TElement,
     {
@@ -195,6 +193,7 @@ where
 
         let mut origins = OriginSet::empty();
         let mut have_invalidations = false;
+
         for (data, origin) in self.invalidation_data.iter_mut_origins() {
             if data.dirty {
                 have_invalidations |= data.invalidations.flush(document_element);
@@ -203,7 +202,7 @@ where
             }
         }
 
-        (self.iter(), origins, have_invalidations)
+        (origins, have_invalidations)
     }
 
     /// Flush stylesheets, but without running any of the invalidation passes.
diff --git a/components/style/stylist.rs b/components/style/stylist.rs
index 2ea8d5313ac..38b0861c047 100644
--- a/components/style/stylist.rs
+++ b/components/style/stylist.rs
@@ -490,13 +490,15 @@ impl Stylist {
         }
 
         let author_style_disabled = self.stylesheets.author_style_disabled();
-        let (doc_stylesheets, origins_to_rebuild, have_invalidations) =
+        let (origins_to_rebuild, have_invalidations) =
             self.stylesheets.flush(document_element);
 
         if origins_to_rebuild.is_empty() {
             return have_invalidations;
         }
 
+        let doc_stylesheets = self.stylesheets.iter();
+
         self.num_rebuilds += 1;
 
         // Update viewport_constraints regardless of which origins'
@@ -520,9 +522,11 @@ impl Stylist {
             };
 
             self.viewport_constraints =
-                ViewportConstraints::maybe_new(&self.device,
-                                               &cascaded_rule,
-                                               self.quirks_mode);
+                ViewportConstraints::maybe_new(
+                    &self.device,
+                    &cascaded_rule,
+                    self.quirks_mode,
+                );
 
             if let Some(ref constraints) = self.viewport_constraints {
                 self.device.account_for_viewport_rule(constraints);