--- a/dom/base/Element.h
+++ b/dom/base/Element.h
@@ -78,38 +78,64 @@ already_AddRefed<nsContentList>
 NS_GetContentList(nsINode* aRootNode,
                   int32_t  aMatchNameSpaceId,
                   const nsAString& aTagname);
 
 #define ELEMENT_FLAG_BIT(n_) NODE_FLAG_BIT(NODE_TYPE_SPECIFIC_BITS_OFFSET + (n_))
 
 // Element-specific flags
 enum {
+  // These two bits are shared by Gecko's and Servo's restyle systems for
+  // different purposes. They should not be accessed directly, and access to
+  // them should be properly guarded by asserts.
+  ELEMENT_SHARED_RESTYLE_BIT_1 = ELEMENT_FLAG_BIT(0),
+  ELEMENT_SHARED_RESTYLE_BIT_2 = ELEMENT_FLAG_BIT(1),
+  ELEMENT_SHARED_RESTYLE_BIT_3 = ELEMENT_FLAG_BIT(2),
+  ELEMENT_SHARED_RESTYLE_BIT_4 = ELEMENT_FLAG_BIT(3),
+
+  // Whether this node has dirty descendants for Servo's style system.
+  ELEMENT_HAS_DIRTY_DESCENDANTS_FOR_SERVO = ELEMENT_SHARED_RESTYLE_BIT_1,
+
+  // Whether this node has dirty descendants for animation-only restyle for
+  // Servo's style system.
+  ELEMENT_HAS_ANIMATION_ONLY_DIRTY_DESCENDANTS_FOR_SERVO =
+    ELEMENT_SHARED_RESTYLE_BIT_2,
+
+  // Whether the element has been snapshotted due to attribute or state changes
+  // by the Servo restyle manager.
+  ELEMENT_HAS_SNAPSHOT = ELEMENT_SHARED_RESTYLE_BIT_3,
+
+  // Whether the element has already handled its relevant snapshot.
+  //
+  // Used by the servo restyle process in order to accurately track whether the
+  // style of an element is up-to-date, even during the same restyle process.
+  ELEMENT_HANDLED_SNAPSHOT = ELEMENT_SHARED_RESTYLE_BIT_4,
+
   // Set if the element has a pending style change.
-  ELEMENT_HAS_PENDING_RESTYLE =                 NODE_SHARED_RESTYLE_BIT_1,
+  ELEMENT_HAS_PENDING_RESTYLE = ELEMENT_SHARED_RESTYLE_BIT_1,
 
   // Set if the element is a potential restyle root (that is, has a style
   // change pending _and_ that style change will attempt to restyle
   // descendants).
-  ELEMENT_IS_POTENTIAL_RESTYLE_ROOT =           NODE_SHARED_RESTYLE_BIT_2,
+  ELEMENT_IS_POTENTIAL_RESTYLE_ROOT = ELEMENT_SHARED_RESTYLE_BIT_2,
 
   // Set if the element has a pending animation-only style change as
   // part of an animation-only style update (where we update styles from
   // animation to the current refresh tick, but leave everything else as
   // it was).
-  ELEMENT_HAS_PENDING_ANIMATION_ONLY_RESTYLE =  ELEMENT_FLAG_BIT(0),
+  ELEMENT_HAS_PENDING_ANIMATION_ONLY_RESTYLE = ELEMENT_SHARED_RESTYLE_BIT_3,
 
   // Set if the element is a potential animation-only restyle root (that
   // is, has an animation-only style change pending _and_ that style
   // change will attempt to restyle descendants).
-  ELEMENT_IS_POTENTIAL_ANIMATION_ONLY_RESTYLE_ROOT = ELEMENT_FLAG_BIT(1),
+  ELEMENT_IS_POTENTIAL_ANIMATION_ONLY_RESTYLE_ROOT = ELEMENT_SHARED_RESTYLE_BIT_4,
 
   // Set if this element has a pending restyle with an eRestyle_SomeDescendants
   // restyle hint.
-  ELEMENT_IS_CONDITIONAL_RESTYLE_ANCESTOR = ELEMENT_FLAG_BIT(2),
+  ELEMENT_IS_CONDITIONAL_RESTYLE_ANCESTOR = ELEMENT_FLAG_BIT(4),
 
   // Just the HAS_PENDING bits, for convenience
   ELEMENT_PENDING_RESTYLE_FLAGS =
     ELEMENT_HAS_PENDING_RESTYLE |
     ELEMENT_HAS_PENDING_ANIMATION_ONLY_RESTYLE,
 
   // Just the IS_POTENTIAL bits, for convenience
   ELEMENT_POTENTIAL_RESTYLE_ROOT_FLAGS =
@@ -117,20 +143,20 @@ enum {
     ELEMENT_IS_POTENTIAL_ANIMATION_ONLY_RESTYLE_ROOT,
 
   // All of the restyle bits together, for convenience.
   ELEMENT_ALL_RESTYLE_FLAGS = ELEMENT_PENDING_RESTYLE_FLAGS |
                               ELEMENT_POTENTIAL_RESTYLE_ROOT_FLAGS |
                               ELEMENT_IS_CONDITIONAL_RESTYLE_ANCESTOR,
 
   // Set if this element is marked as 'scrollgrab' (see bug 912666)
-  ELEMENT_HAS_SCROLLGRAB = ELEMENT_FLAG_BIT(3),
+  ELEMENT_HAS_SCROLLGRAB = ELEMENT_FLAG_BIT(5),
 
   // Remaining bits are for subclasses
-  ELEMENT_TYPE_SPECIFIC_BITS_OFFSET = NODE_TYPE_SPECIFIC_BITS_OFFSET + 4
+  ELEMENT_TYPE_SPECIFIC_BITS_OFFSET = NODE_TYPE_SPECIFIC_BITS_OFFSET + 6
 };
 
 #undef ELEMENT_FLAG_BIT
 
 // Make sure we have space for our bits
 ASSERT_NODE_FLAGS_SPACE(ELEMENT_TYPE_SPECIFIC_BITS_OFFSET);
 
 namespace mozilla {
@@ -434,27 +460,27 @@ public:
   Directionality GetComputedDirectionality() const;
 
   inline Element* GetFlattenedTreeParentElement() const;
   inline Element* GetFlattenedTreeParentElementForStyle() const;
 
   bool HasDirtyDescendantsForServo() const
   {
     MOZ_ASSERT(IsStyledByServo());
-    return HasFlag(NODE_HAS_DIRTY_DESCENDANTS_FOR_SERVO);
+    return HasFlag(ELEMENT_HAS_DIRTY_DESCENDANTS_FOR_SERVO);
   }
 
   void SetHasDirtyDescendantsForServo() {
     MOZ_ASSERT(IsStyledByServo());
-    SetFlags(NODE_HAS_DIRTY_DESCENDANTS_FOR_SERVO);
+    SetFlags(ELEMENT_HAS_DIRTY_DESCENDANTS_FOR_SERVO);
   }
 
   void UnsetHasDirtyDescendantsForServo() {
     MOZ_ASSERT(IsStyledByServo());
-    UnsetFlags(NODE_HAS_DIRTY_DESCENDANTS_FOR_SERVO);
+    UnsetFlags(ELEMENT_HAS_DIRTY_DESCENDANTS_FOR_SERVO);
   }
 
   inline void NoteDirtyDescendantsForServo();
 
 #ifdef DEBUG
   inline bool DirtyDescendantsBitIsPropagatedForServo();
 #endif
 

--- a/dom/base/nsINode.h
+++ b/dom/base/nsINode.h
@@ -198,34 +198,18 @@ enum {
 
   NODE_ALL_DIRECTION_FLAGS =              NODE_HAS_DIRECTION_LTR |
                                           NODE_HAS_DIRECTION_RTL,
 
   NODE_CHROME_ONLY_ACCESS =               NODE_FLAG_BIT(19),
 
   NODE_IS_ROOT_OF_CHROME_ONLY_ACCESS =    NODE_FLAG_BIT(20),
 
-  // These two bits are shared by Gecko's and Servo's restyle systems for
-  // different purposes. They should not be accessed directly, and access to
-  // them should be properly guarded by asserts.
-  //
-  // FIXME(bholley): These should move to Element, and we only need one now.
-  NODE_SHARED_RESTYLE_BIT_1 =             NODE_FLAG_BIT(21),
-  NODE_SHARED_RESTYLE_BIT_2 =             NODE_FLAG_BIT(22),
-
-  // Whether this node has dirty descendants for Servo's style system.
-  NODE_HAS_DIRTY_DESCENDANTS_FOR_SERVO =  NODE_SHARED_RESTYLE_BIT_1,
-
-  // Whether this node has dirty descendants for animation-only restyle for
-  // Servo's style system.
-  NODE_HAS_ANIMATION_ONLY_DIRTY_DESCENDANTS_FOR_SERVO =
-    NODE_SHARED_RESTYLE_BIT_2,
-
   // Remaining bits are node type specific.
-  NODE_TYPE_SPECIFIC_BITS_OFFSET =        23
+  NODE_TYPE_SPECIFIC_BITS_OFFSET =        21
 };
 
 // Make sure we have space for our bits
 #define ASSERT_NODE_FLAGS_SPACE(n) \
   static_assert(WRAPPER_CACHE_FLAGS_BITS_USED + (n) <=                          \
                   sizeof(nsWrapperCache::FlagsType) * 8,                        \
                 "Not enough space for our bits")
 ASSERT_NODE_FLAGS_SPACE(NODE_TYPE_SPECIFIC_BITS_OFFSET);