Break dependency between ChromeClient and WebViewImpl, and ChromeClientImpl.

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

 /*
  * Copyright (C) 2006 Eric Seidel (eric@webkit.org)
  * Copyright (C) 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  * Copyright (C) 2012 Samsung Electronics. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
@@ skipping 215 matching lines @@
     return nullptr;
   }
 
   AnimationWorkletProxyClient* CreateAnimationWorkletProxyClient(
       LocalFrame*) override {
     return nullptr;
   }
 
   void RegisterPopupOpeningObserver(PopupOpeningObserver*) override {}
   void UnregisterPopupOpeningObserver(PopupOpeningObserver*) override {}
+  void NotifyPopupOpeningObservers() const {}
 
   std::unique_ptr<WebFrameScheduler> CreateFrameScheduler(
       BlameContext*) override;
 };
 
 class CORE_EXPORT EmptyLocalFrameClient : public LocalFrameClient {
   WTF_MAKE_NONCOPYABLE(EmptyLocalFrameClient);
 
  public:
   static EmptyLocalFrameClient* Create() { return new EmptyLocalFrameClient; }
@@ skipping 224 matching lines @@
   Frame* NextSibling() const override { return nullptr; }
   Frame* FirstChild() const override { return nullptr; }
   void FrameFocused() const override {}
 };
 
 CORE_EXPORT void FillWithEmptyClients(Page::PageClients&);
 
 }  // namespace blink
 
 #endif  // EmptyClients_h