IntersectionObserver: Always send an initial notification.

third_party/WebKit/Source/core/dom/IntersectionObserver.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef IntersectionObserver_h
 #define IntersectionObserver_h
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "core/dom/IntersectionObservation.h"
@@ skipping 14 matching lines @@
 class CORE_EXPORT IntersectionObserver final
     : public GarbageCollectedFinalized<IntersectionObserver>,
       public ScriptWrappable {
   DEFINE_WRAPPERTYPEINFO();
 
  public:
   using EventCallback =
       Function<void(const HeapVector<Member<IntersectionObserverEntry>>&),
                WTF::SameThreadAffinity>;
 
-  // Defines the assumed initial state of the observed element. If the actual
-  // state is the same as the initial state, then no observation will be
-  // delivered. kAuto means the initial observation will always get sent.
-  enum InitialState {
-    // TODO(skyostil): Add support for kVisible.
-    kAuto = 0,
-    kHidden = 1,
-    kDoNotUseMax = 2
-  };
-
-  // InitialState is stored in a single bit in m_initialState.  If adding new
-  // enum values, increase the size of m_initialState and update the assert.
-  static_assert(InitialState::kDoNotUseMax == 2,
-                "InitialState fits in a single bit.");
-
   static IntersectionObserver* create(const IntersectionObserverInit&,
                                       IntersectionObserverCallback&,
                                       ExceptionState&);
   static IntersectionObserver* create(const Vector<Length>& rootMargin,
                                       const Vector<float>& thresholds,
                                       Document*,
                                       std::unique_ptr<EventCallback>,
                                       ExceptionState& = ASSERT_NO_EXCEPTION);
   static void resumeSuspendedObservers();
 
@@ skipping 26 matching lines @@
   void computeIntersectionObservations();
   void enqueueIntersectionObserverEntry(IntersectionObserverEntry&);
   unsigned firstThresholdGreaterThan(float ratio) const;
   void deliver();
   bool hasEntries() const { return m_entries.size(); }
   const HeapLinkedHashSet<WeakMember<IntersectionObservation>>& observations()
       const {
     return m_observations;
   }
 
-  // Set the assumed initial state of the observed element. Note that this can
-  // only be set before calling observe().
-  // TODO(skyostil): Move this setting to IntersectionObserverInit once the API
-  // is finalized.
-  void setInitialState(InitialState);
-
   DECLARE_TRACE();
 
  private:
   explicit IntersectionObserver(IntersectionObserverCallback&,
                                 Element*,
                                 const Vector<Length>& rootMargin,
                                 const Vector<float>& thresholds);
   void clearWeakMembers(Visitor*);
 
   // Returns false if this observer has an explicit root element which has been
   // deleted; true otherwise.
   bool rootIsValid() const;
 
   Member<IntersectionObserverCallback> m_callback;
   WeakMember<Element> m_root;
   HeapLinkedHashSet<WeakMember<IntersectionObservation>> m_observations;
   HeapVector<Member<IntersectionObserverEntry>> m_entries;
   Vector<float> m_thresholds;
   Length m_topMargin;
   Length m_rightMargin;
   Length m_bottomMargin;
   Length m_leftMargin;
   unsigned m_rootIsImplicit : 1;
-  // m_initialState contains values from enum InitialState
-  unsigned m_initialState : 1;
 };
 
 }  // namespace blink
 
 #endif  // IntersectionObserver_h