[IntersectionObserver] Get rid of spurious console warning.

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 224 matching lines @@
   if (!target || root() == target)
     return;
 
   LocalFrame* targetFrame = target->document().frame();
   if (!targetFrame)
     return;
 
   if (target->ensureIntersectionObserverData().getObservationFor(*this))
     return;
 
-  bool isDOMDescendant = true;
-  bool shouldReportRootBounds = false;
+  bool shouldReportRootBounds = true;
   if (rootIsImplicit()) {
     Frame* rootFrame = targetFrame->tree().top();
     DCHECK(rootFrame);
-    if (rootFrame == targetFrame) {
-      shouldReportRootBounds = true;
-    } else {
+    if (rootFrame != targetFrame) {
       shouldReportRootBounds =
           targetFrame->securityContext()->getSecurityOrigin()->canAccess(
               rootFrame->securityContext()->getSecurityOrigin());
     }
-  } else {
-    shouldReportRootBounds = true;
-    isDOMDescendant = root()->isShadowIncludingInclusiveAncestorOf(target);
   }
 
   IntersectionObservation* observation =
       new IntersectionObservation(*this, *target, shouldReportRootBounds);
   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 (FrameView* frameView = targetFrame->view())
     frameView->scheduleAnimation();
 }
 
 void IntersectionObserver::unobserve(Element* target,
                                      ExceptionState& exceptionState) {
   if (!target || !target->intersectionObserverData())
     return;
 
   if (IntersectionObservation* observation =
@@ skipping 78 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