IntersectionObserver: Always send an initial notification.

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

 // 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.
 
 #include "core/dom/IntersectionObserver.h"
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "core/css/parser/CSSParserTokenRange.h"
 #include "core/css/parser/CSSTokenizer.h"
 #include "core/dom/Element.h"
@@ skipping 155 matching lines @@
     Element* root,
     const Vector<Length>& rootMargin,
     const Vector<float>& thresholds)
     : m_callback(&callback),
       m_root(root),
       m_thresholds(thresholds),
       m_topMargin(Fixed),
       m_rightMargin(Fixed),
       m_bottomMargin(Fixed),
       m_leftMargin(Fixed),
-      m_rootIsImplicit(root ? 0 : 1),
-      m_initialState(InitialState::kHidden) {
+      m_rootIsImplicit(root ? 0 : 1) {
   switch (rootMargin.size()) {
     case 0:
       break;
     case 1:
       m_topMargin = m_rightMargin = m_bottomMargin = m_leftMargin =
           rootMargin[0];
       break;
     case 2:
       m_topMargin = m_bottomMargin = rootMargin[0];
       m_rightMargin = m_leftMargin = rootMargin[1];
@@ skipping 77 matching lines @@
   target->ensureIntersectionObserverData().addObservation(*observation);
   m_observations.add(observation);
 
   if (!isDOMDescendant) {
     root()->document().addConsoleMessage(
         ConsoleMessage::create(JSMessageSource, WarningMessageLevel,
                                "IntersectionObserver.observe(target): target "
                                "element is not a descendant of root."));
   }
 
-  if (m_initialState == InitialState::kAuto) {
-    for (auto& observation : m_observations)
-      observation->setLastThresholdIndex(std::numeric_limits<unsigned>::max());
-  }
-
   if (FrameView* frameView = targetFrame->view())
     frameView->scheduleAnimation();
 }
 
 void IntersectionObserver::unobserve(Element* target,
                                      ExceptionState& exceptionState) {
   if (!target || !target->intersectionObserverData())
     return;
 
   if (IntersectionObservation* observation =
@@ skipping 17 matching lines @@
   for (auto& observation : m_observations)
     observation->computeIntersectionObservations(timestamp);
 }
 
 void IntersectionObserver::disconnect(ExceptionState& exceptionState) {
   for (auto& observation : m_observations)
     observation->disconnect();
   m_observations.clear();
 }
 
-void IntersectionObserver::setInitialState(InitialState initialState) {
-  DCHECK(m_observations.isEmpty());
-  m_initialState = initialState;
-}
-
 HeapVector<Member<IntersectionObserverEntry>> IntersectionObserver::takeRecords(
     ExceptionState& exceptionState) {
   HeapVector<Member<IntersectionObserverEntry>> entries;
   entries.swap(m_entries);
   return entries;
 }
 
 static void appendLength(StringBuilder& stringBuilder, const Length& length) {
   stringBuilder.appendNumber(length.intValue());
   if (length.type() == Percent)
@@ skipping 40 matching lines @@
 
 DEFINE_TRACE(IntersectionObserver) {
   visitor->template registerWeakMembers<
       IntersectionObserver, &IntersectionObserver::clearWeakMembers>(this);
   visitor->trace(m_callback);
   visitor->trace(m_observations);
   visitor->trace(m_entries);
 }
 
 }  // namespace blink