Intersection Observer support for OOPIF

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

Index: third_party/WebKit/Source/core/dom/IntersectionObserver.cpp
diff --git a/third_party/WebKit/Source/core/dom/IntersectionObserver.cpp b/third_party/WebKit/Source/core/dom/IntersectionObserver.cpp
index 7509dcf7051d0c111c615918360c489eed7e098e..e04ca3394f6b48c3eb06b25708f1decc3c23e15c 100644
--- a/third_party/WebKit/Source/core/dom/IntersectionObserver.cpp
+++ b/third_party/WebKit/Source/core/dom/IntersectionObserver.cpp
@@ -132,11 +132,10 @@ void parseThresholds(const DoubleOrDoubleSequence& thresholdParameter,
 
 // Returns the root Node of a given Document to use as the IntersectionObserver
 // root when no root is given.
-// TODO(szager): it doesn't support RemoteFrames, see https://crbug.com/615156
 Node* getRootNode(Document* document) {
-  Frame* mainFrame = document->frame()->tree().top();
-  if (mainFrame && mainFrame->isLocalFrame())
-    return toLocalFrame(mainFrame)->document();
+  LocalFrame* rootFrame = document->frame()->localFrameRoot();
+  if (rootFrame)
+    return rootFrame->document();
   return nullptr;
 }
 
@@ -146,11 +145,17 @@ IntersectionObserver* IntersectionObserver::create(
     const IntersectionObserverInit& observerInit,
     IntersectionObserverCallback& callback,
     ExceptionState& exceptionState) {
+  bool intersectWithRemoteAncestors = false;
   Node* root = observerInit.root();
   if (!root) {
     ExecutionContext* context = callback.getExecutionContext();
     DCHECK(context->isDocument());
     root = getRootNode(toDocument(context));
+    if (root && (toDocument(context)->frame()->tree().top()->isRemoteFrame() ||
+                 root !=
+                     toLocalFrame(toDocument(context)->frame()->tree().top())
+                         ->document()))
+      intersectWithRemoteAncestors = true;
   }
   if (!root) {
     exceptionState.throwDOMException(
@@ -169,7 +174,8 @@ IntersectionObserver* IntersectionObserver::create(
   if (exceptionState.hadException())
     return nullptr;
 
-  return new IntersectionObserver(callback, *root, rootMargin, thresholds);
+  return new IntersectionObserver(callback, *root, rootMargin, thresholds,
+                                  intersectWithRemoteAncestors);
 }
 
 IntersectionObserver* IntersectionObserver::create(
@@ -179,6 +185,11 @@ IntersectionObserver* IntersectionObserver::create(
     std::unique_ptr<EventCallback> callback,
     ExceptionState& exceptionState) {
   Node* root = getRootNode(document);
+  bool intersectWithRemoteAncestors = false;
+  if (root &&
+      (document->frame()->tree().top()->isRemoteFrame() ||
+       root != toLocalFrame(document->frame()->tree().top())->document()))
+    intersectWithRemoteAncestors = true;
   if (!root) {
     exceptionState.throwDOMException(
         HierarchyRequestError,
@@ -189,21 +200,24 @@ IntersectionObserver* IntersectionObserver::create(
   IntersectionObserverCallbackImpl* intersectionObserverCallback =
       new IntersectionObserverCallbackImpl(document, std::move(callback));
   return new IntersectionObserver(*intersectionObserverCallback, *root,
-                                  rootMargin, thresholds);
+                                  rootMargin, thresholds,
+                                  intersectWithRemoteAncestors);
 }
 
 IntersectionObserver::IntersectionObserver(
     IntersectionObserverCallback& callback,
     Node& root,
     const Vector<Length>& rootMargin,
-    const Vector<float>& thresholds)
+    const Vector<float>& thresholds,
+    bool intersectWithRemoteAncestors)
     : m_callback(&callback),
       m_root(&root),
       m_thresholds(thresholds),
       m_topMargin(Fixed),
       m_rightMargin(Fixed),
       m_bottomMargin(Fixed),
-      m_leftMargin(Fixed) {
+      m_leftMargin(Fixed),
+      m_intersectWithRemoteAncestors(intersectWithRemoteAncestors) {
   switch (rootMargin.size()) {
     case 0:
       break;
@@ -269,7 +283,8 @@ void IntersectionObserver::observe(Element* target,
   LocalFrame* rootFrame = m_root->document().frame();
 
   if (target->document() == rootNode()->document()) {
-    shouldReportRootBounds = true;
+    if (!m_intersectWithRemoteAncestors)
+      shouldReportRootBounds = true;
     isDOMDescendant = rootNode()->isShadowIncludingInclusiveAncestorOf(target);
   } else if (targetFrame && rootFrame) {
     shouldReportRootBounds =
@@ -434,6 +449,18 @@ void IntersectionObserver::deliver() {
   m_callback->handleEvent(entries, *this);
 }
 
+void IntersectionObserver::intersectWithRemoteAncestorsIfNeeded(
+    LayoutRect& rect) {
+  if (m_intersectWithRemoteAncestors) {
+    Document* root = toDocument(rootNode());
+    if (root->view()) {
+      LayoutRect viewportIntersectionRect(
+          root->view()->remoteViewportIntersection());
+      rect.intersect(viewportIntersectionRect);
+    }
+  }
+}
+
 DEFINE_TRACE(IntersectionObserver) {
   visitor->template registerWeakMembers<
       IntersectionObserver, &IntersectionObserver::clearWeakMembers>(this);