Change TreeOrderedMap to accept a reference instead of a pointer

This CL also changes a few other related pieces of code to use references
as necessary.

Change-Id: I8aaf0dd00e3f56819244a8b6dbdd6c2f758bee64
Reviewed-on: https://chromium-review.googlesource.com/1175592Reviewed-by: Kent Tamura <tkent@chromium.org>
Commit-Queue: Hayato Ito <hayato@chromium.org>
Cr-Commit-Position: refs/heads/master@{#583201}

third_party/blink/renderer/core/dom/element.cc

@@ -4452,9 +4452,9 @@ inline void Element::UpdateId(TreeScope& scope,
   DCHECK_NE(old_id, new_id);
 
   if (!old_id.IsEmpty())
-    scope.RemoveElementById(old_id, this);
+    scope.RemoveElementById(old_id, *this);
   if (!new_id.IsEmpty())
-    scope.AddElementById(new_id, this);
+    scope.AddElementById(new_id, *this);
 
   NamedItemType type = GetNamedItemType();
   if (type == NamedItemType::kNameOrId ||

third_party/blink/renderer/core/dom/slot_assignment.cc

@@ -83,7 +83,7 @@ void SlotAssignment::DidAddSlotInternal(HTMLSlotElement& slot) {
   DCHECK(!old_active || old_active != slot);
 
   // This might invalidate the slot_map's cache.
-  slot_map_->Add(slot_name, &slot);
+  slot_map_->Add(slot_name, slot);
 
   // This also ensures that TreeOrderedMap has a cache for the first element.
   HTMLSlotElement* new_active = FindSlotByName(slot_name);
@@ -130,7 +130,7 @@ void SlotAssignment::DidRemoveSlotInternal(
   HTMLSlotElement* old_active =
       GetCachedFirstSlotWithoutAccessingNodeTree(slot_name);
   DCHECK(old_active);
-  slot_map_->Remove(slot_name, &slot);
+  slot_map_->Remove(slot_name, slot);
   // This also ensures that TreeOrderedMap has a cache for the first element.
   HTMLSlotElement* new_active = FindSlotByName(slot_name);
   DCHECK(!new_active || new_active != slot);

third_party/blink/renderer/core/dom/tree_ordered_map.cc

@@ -76,9 +76,8 @@ inline bool KeyMatchesSlotName(const AtomicString& key,
          ToHTMLSlotElement(element).GetName() == key;
 }
 
-void TreeOrderedMap::Add(const AtomicString& key, Element* element) {
+void TreeOrderedMap::Add(const AtomicString& key, Element& element) {
   DCHECK(key);
-  DCHECK(element);
 
   Map::AddResult add_result = map_.insert(key, new MapEntry(element));
   if (add_result.is_new_entry)
@@ -91,9 +90,8 @@ void TreeOrderedMap::Add(const AtomicString& key, Element* element) {
   entry->ordered_list.clear();
 }
 
-void TreeOrderedMap::Remove(const AtomicString& key, Element* element) {
+void TreeOrderedMap::Remove(const AtomicString& key, Element& element) {
   DCHECK(key);
-  DCHECK(element);
 
   Map::iterator it = map_.find(key);
   if (it == map_.end())

third_party/blink/renderer/core/dom/tree_ordered_map.h

@@ -50,8 +50,8 @@ class TreeOrderedMap : public GarbageCollected<TreeOrderedMap> {
  public:
   static TreeOrderedMap* Create();
 
-  void Add(const AtomicString&, Element*);
-  void Remove(const AtomicString&, Element*);
+  void Add(const AtomicString&, Element&);
+  void Remove(const AtomicString&, Element&);
 
   bool Contains(const AtomicString&) const;
   bool ContainsMultiple(const AtomicString&) const;
@@ -98,7 +98,7 @@ class TreeOrderedMap : public GarbageCollected<TreeOrderedMap> {
 
   class MapEntry : public GarbageCollected<MapEntry> {
    public:
-    explicit MapEntry(Element* first_element)
+    explicit MapEntry(Element& first_element)
         : element(first_element), count(1) {}
 
     void Trace(blink::Visitor*);

third_party/blink/renderer/core/dom/tree_scope.cc

@@ -137,7 +137,7 @@ const HeapVector<Member<Element>>& TreeScope::GetAllElementsById(
 }
 
 void TreeScope::AddElementById(const AtomicString& element_id,
-                               Element* element) {
+                               Element& element) {
   if (!elements_by_id_)
     elements_by_id_ = TreeOrderedMap::Create();
   elements_by_id_->Add(element_id, element);
@@ -145,7 +145,7 @@ void TreeScope::AddElementById(const AtomicString& element_id,
 }
 
 void TreeScope::RemoveElementById(const AtomicString& element_id,
-                                  Element* element) {
+                                  Element& element) {
   if (!elements_by_id_)
     return;
   elements_by_id_->Remove(element_id, element);
@@ -165,8 +165,8 @@ Node* TreeScope::AncestorInThisScope(Node* node) const {
   return nullptr;
 }
 
-void TreeScope::AddImageMap(HTMLMapElement* image_map) {
-  const AtomicString& name = image_map->GetName();
+void TreeScope::AddImageMap(HTMLMapElement& image_map) {
+  const AtomicString& name = image_map.GetName();
   if (!name)
     return;
   if (!image_maps_by_name_)
@@ -174,10 +174,10 @@ void TreeScope::AddImageMap(HTMLMapElement* image_map) {
   image_maps_by_name_->Add(name, image_map);
 }
 
-void TreeScope::RemoveImageMap(HTMLMapElement* image_map) {
+void TreeScope::RemoveImageMap(HTMLMapElement& image_map) {
   if (!image_maps_by_name_)
     return;
-  const AtomicString& name = image_map->GetName();
+  const AtomicString& name = image_map.GetName();
   if (!name)
     return;
   image_maps_by_name_->Remove(name, image_map);

third_party/blink/renderer/core/dom/tree_scope.h

@@ -76,8 +76,8 @@ class CORE_EXPORT TreeScope : public GarbageCollectedMixin {
       const AtomicString&) const;
   bool HasElementWithId(const AtomicString& id) const;
   bool ContainsMultipleElementsWithId(const AtomicString& id) const;
-  void AddElementById(const AtomicString& element_id, Element*);
-  void RemoveElementById(const AtomicString& element_id, Element*);
+  void AddElementById(const AtomicString& element_id, Element&);
+  void RemoveElementById(const AtomicString& element_id, Element&);
 
   Document& GetDocument() const {
     DCHECK(document_);
@@ -86,8 +86,8 @@ class CORE_EXPORT TreeScope : public GarbageCollectedMixin {
 
   Node* AncestorInThisScope(Node*) const;
 
-  void AddImageMap(HTMLMapElement*);
-  void RemoveImageMap(HTMLMapElement*);
+  void AddImageMap(HTMLMapElement&);
+  void RemoveImageMap(HTMLMapElement&);
   HTMLMapElement* GetImageMap(const String& url) const;
 
   Element* ElementFromPoint(double x, double y) const;

third_party/blink/renderer/core/html/html_map_element.cc

@@ -87,13 +87,13 @@ void HTMLMapElement::ParseAttribute(const AttributeModificationParams& params) {
         return;
     }
     if (isConnected())
-      GetTreeScope().RemoveImageMap(this);
+      GetTreeScope().RemoveImageMap(*this);
     String map_name = params.new_value;
     if (map_name[0] == '#')
       map_name = map_name.Substring(1);
     name_ = AtomicString(map_name);
     if (isConnected())
-      GetTreeScope().AddImageMap(this);
+      GetTreeScope().AddImageMap(*this);
 
     return;
   }
@@ -108,13 +108,13 @@ HTMLCollection* HTMLMapElement::areas() {
 Node::InsertionNotificationRequest HTMLMapElement::InsertedInto(
     ContainerNode* insertion_point) {
   if (insertion_point->isConnected())
-    GetTreeScope().AddImageMap(this);
+    GetTreeScope().AddImageMap(*this);
   return HTMLElement::InsertedInto(insertion_point);
 }
 
 void HTMLMapElement::RemovedFrom(ContainerNode* insertion_point) {
   if (insertion_point->isConnected())
-    GetTreeScope().RemoveImageMap(this);
+    GetTreeScope().RemoveImageMap(*this);
   HTMLElement::RemovedFrom(insertion_point);
 }