servo: Merge #18246 - stylo: followup fixes for restyle roots (from bholley:restyle_root_followups); r=emilio

https://bugzilla.mozilla.org/show_bug.cgi?id=1392863

Source-Repo: https://github.com/servo/servo
Source-Revision: 1fd0edf158bb479b420fb6ddc76470d82c88cb61

--HG--
extra : subtree_source : https%3A//hg.mozilla.org/projects/converted-servo-linear
extra : subtree_revision : e8f1719c27589efb90b7f844eadaa4ed68b62137

servo/components/style/dom.rs

@@ -506,7 +506,7 @@ pub trait TElement : Eq + PartialEq + Debug + Hash + Sized + Copy + Clone +
     /// In Gecko, this corresponds to the regular dirty descendants bit, the
     /// animation-only dirty descendants bit, and the lazy frame construction
     /// descendants bit.
-    unsafe fn clear_descendants_bits(&self) { self.unset_dirty_descendants(); }
+    unsafe fn clear_descendant_bits(&self) { self.unset_dirty_descendants(); }
 
     /// Clear all element flags related to dirtiness.
     ///

servo/components/style/gecko/wrapper.rs

@@ -1094,7 +1094,7 @@ impl<'le> TElement for GeckoElement<'le> {
         self.unset_flags(ELEMENT_HAS_ANIMATION_ONLY_DIRTY_DESCENDANTS_FOR_SERVO as u32)
     }
 
-    unsafe fn clear_descendants_bits(&self) {
+    unsafe fn clear_descendant_bits(&self) {
         self.unset_flags(ELEMENT_HAS_DIRTY_DESCENDANTS_FOR_SERVO as u32 |
                          ELEMENT_HAS_ANIMATION_ONLY_DIRTY_DESCENDANTS_FOR_SERVO as u32 |
                          NODE_DESCENDANTS_NEED_FRAMES as u32)
@@ -1159,7 +1159,9 @@ impl<'le> TElement for GeckoElement<'le> {
         let ptr = self.0.mServoData.get();
         unsafe {
             self.unset_flags(ELEMENT_HAS_SNAPSHOT as u32 |
-                             ELEMENT_HANDLED_SNAPSHOT as u32);
+                             ELEMENT_HANDLED_SNAPSHOT as u32 |
+                             structs::Element_kAllServoDescendantBits |
+                             NODE_NEEDS_FRAME as u32);
         }
         if !ptr.is_null() {
             debug!("Dropping ElementData for {:?}", self);

servo/components/style/traversal.rs

@@ -878,11 +878,8 @@ where
                 }
             }
         }
-        if p == root {
-            // Make sure not to clear NODE_NEEDS_FRAME on the root.
-            p.clear_descendants_bits();
-        } else {
-            p.clear_dirty_bits();
-        }
     }
+
+    // Make sure not to clear NODE_NEEDS_FRAME on the root.
+    root.clear_descendant_bits();
 }