Cleanup remaining class/struct fwd declarations

headless/lib/browser/headless_web_contents_impl.h

 // Copyright 2015 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.
 
 #ifndef HEADLESS_LIB_BROWSER_HEADLESS_WEB_CONTENTS_IMPL_H_
 #define HEADLESS_LIB_BROWSER_HEADLESS_WEB_CONTENTS_IMPL_H_
 
 #include <list>
 #include <memory>
 #include <string>
 #include <unordered_map>
 
 #include "content/public/browser/render_process_host_observer.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "headless/public/headless_devtools_target.h"
 #include "headless/public/headless_web_contents.h"
 
 namespace aura {
 class Window;
 }
 
 namespace content {
-class BrowserContext;
 class DevToolsAgentHost;
 class WebContents;
 }
 
 namespace gfx {
 class Size;
 }
 
 namespace headless {
-class HeadlessDevToolsHostImpl;
 class HeadlessBrowserImpl;
 class WebContentsObserverAdapter;
 
 class HeadlessWebContentsImpl : public HeadlessWebContents,
                                 public HeadlessDevToolsTarget,
                                 public content::RenderProcessHostObserver,
                                 public content::WebContentsObserver {
  public:
   ~HeadlessWebContentsImpl() override;
 
@@ skipping 61 matching lines @@
       std::unordered_map<HeadlessWebContents::Observer*,
                          std::unique_ptr<WebContentsObserverAdapter>>;
   ObserverMap observer_map_;
 
   DISALLOW_COPY_AND_ASSIGN(HeadlessWebContentsImpl);
 };
 
 }  // namespace headless
 
 #endif  // HEADLESS_LIB_BROWSER_HEADLESS_WEB_CONTENTS_IMPL_H_