ElementVisibilityObserver: remove OOPIF checks.

third_party/WebKit/Source/core/loader/EmptyClients.h

Index: third_party/WebKit/Source/core/loader/EmptyClients.h
diff --git a/third_party/WebKit/Source/core/loader/EmptyClients.h b/third_party/WebKit/Source/core/loader/EmptyClients.h
index 416e2c10552d2163e838385a79c22d0d77b42b26..0c022901d9b2542c9b08b945332aec49fbbf396c 100644
--- a/third_party/WebKit/Source/core/loader/EmptyClients.h
+++ b/third_party/WebKit/Source/core/loader/EmptyClients.h
@@ -30,6 +30,7 @@
 #define EmptyClients_h
 
 #include "core/CoreExport.h"
+#include "core/frame/RemoteFrameClient.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/ContextMenuClient.h"
@@ -423,6 +424,42 @@ class EmptyContextMenuClient final : public ContextMenuClient {
   void clearContextMenu() override {}
 };
 
+class CORE_EXPORT EmptyRemoteFrameClient
+    : NON_EXPORTED_BASE(public RemoteFrameClient) {
+  WTF_MAKE_NONCOPYABLE(EmptyRemoteFrameClient);
+
+ public:
+  EmptyRemoteFrameClient();
+
+  // RemoteFrameClient implementation.
+  void navigate(const ResourceRequest&,
+                bool shouldReplaceCurrentEntry) override {}
+  void reload(FrameLoadType, ClientRedirectPolicy) override {}
+  unsigned backForwardLength() override { return 0; }
+  void forwardPostMessage(MessageEvent*,
+                          PassRefPtr<SecurityOrigin> target,
+                          LocalFrame* sourceFrame) const override {}
+  void forwardInputEvent(Event*) override {}
+  void frameRectsChanged(const IntRect& frameRect) override {}
+  void updateRemoteViewportIntersection(
+      const IntRect& viewportIntersection) override {}
+  void advanceFocus(WebFocusType, LocalFrame* source) override {}
+  void visibilityChanged(bool visible) override {}
+  void setHasReceivedUserGesture() override {}
+
+  // FrameClient implementation.
+  bool inShadowTree() const override { return false; }
+  void willBeDetached() override {}
+  void detached(FrameDetachType) override {}
+  Frame* opener() const override { return nullptr; }
+  void setOpener(Frame*) override {}
+  Frame* parent() const override { return nullptr; }
+  Frame* top() const override { return nullptr; }
+  Frame* nextSibling() const override { return nullptr; }
+  Frame* firstChild() const override { return nullptr; }
+  void frameFocused() const override {}
+};
+
 CORE_EXPORT void fillWithEmptyClients(Page::PageClients&);
 
 }  // namespace blink