ElementVisibilityObserver: remove OOPIF checks.

third_party/WebKit/Source/core/dom/ElementVisibilityObserverTest.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/ElementVisibilityObserver.h"
 
 #include "core/dom/DOMImplementation.h"
 #include "core/dom/Document.h"
+#include "core/frame/RemoteFrame.h"
 #include "core/html/HTMLDivElement.h"
 #include "core/html/HTMLDocument.h"
+#include "core/loader/EmptyClients.h"
 #include "core/testing/DummyPageHolder.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blink {
 
 namespace {
 
+// Stub implementation of FrameLoaderClient for the purpose of testing. It will
+// alow callers to set the parent/top frames by calling |setParent|. It is used
+// in ElementVisibilityObserverTest in order to mock a RemoteFrame parent of a
+// LocalFrame.
+class StubFrameLoaderClient final : public EmptyFrameLoaderClient {
+ public:
+  Frame* parent() const override { return m_parent; }
+  Frame* top() const override { return m_parent; }
+
+  void setParent(Frame* frame) { m_parent = frame; }
+
+  DEFINE_INLINE_VIRTUAL_TRACE() {
+    visitor->trace(m_parent);
+    EmptyFrameLoaderClient::trace(visitor);
+  }
+
+ private:
+  WeakMember<Frame> m_parent = nullptr;
+};
+
 class ElementVisibilityObserverTest : public ::testing::Test {
  protected:
-  void SetUp() override { m_dummyPageHolder = DummyPageHolder::create(); }
+  void SetUp() override {
+    m_frameLoaderClient = new StubFrameLoaderClient();
+    m_dummyPageHolder = DummyPageHolder::create(
+        IntSize(), nullptr, m_frameLoaderClient, nullptr, nullptr);
+  }
+
+  void TearDown() override {
+    m_dummyPageHolder->frame().detach(FrameDetachType::Remove);
+  }
 
   Document& document() { return m_dummyPageHolder->document(); }
+  FrameHost& frameHost() { return m_dummyPageHolder->page().frameHost(); }
+  StubFrameLoaderClient* frameLoaderClient() const {
+    return m_frameLoaderClient;
+  }
 
  private:
   std::unique_ptr<DummyPageHolder> m_dummyPageHolder;
+  Persistent<StubFrameLoaderClient> m_frameLoaderClient;
 };
 
 TEST_F(ElementVisibilityObserverTest, ObserveElementWithoutDocumentFrame) {
   HTMLElement* element = HTMLDivElement::create(
       *DOMImplementation::create(document())->createHTMLDocument("test"));
   ElementVisibilityObserver* observer =
       new ElementVisibilityObserver(element, nullptr);
   observer->start();
   observer->stop();
   // It should not crash.
 }
 
+TEST_F(ElementVisibilityObserverTest, ObserveElementInRemoteFrame) {
+  Persistent<RemoteFrame> remoteFrame =
+      RemoteFrame::create(new EmptyRemoteFrameClient(), &frameHost(), nullptr);
+  frameLoaderClient()->setParent(remoteFrame);
+
+  Persistent<HTMLElement> element = HTMLDivElement::create(document());
+  ElementVisibilityObserver* observer =
+      new ElementVisibilityObserver(element, WTF::bind([](bool) {}));
+  observer->start();
+  observer->deliverObservationsForTesting();
+  observer->stop();
+  // It should not crash.
+}
+
 }  // anonymous namespace
 
 }  // blink namespace