content: Cleanup class/struct forward declarations

content/browser/frame_host/render_frame_host_impl.h

 // Copyright 2013 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 CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_IMPL_H_
 #define CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 40 matching lines @@
 struct AccessibilityHostMsg_FindInPageResultParams;
 struct AccessibilityHostMsg_LocationChangeParams;
 struct FrameHostMsg_DidFailProvisionalLoadWithError_Params;
 struct FrameHostMsg_OpenURL_Params;
 struct FrameMsg_TextTrackSettings_Params;
 #if defined(USE_EXTERNAL_POPUP_MENU)
 struct FrameHostMsg_ShowPopup_Params;
 #endif
 
 namespace base {
-class FilePath;
 class ListValue;
 }
 
 namespace blink {
 namespace mojom {
 class WebBluetoothService;
 }
 }
 
 namespace gfx {
@@ skipping 17 matching lines @@
 class RenderWidgetHostView;
 class RenderWidgetHostViewBase;
 class ResourceRequestBody;
 class StreamHandle;
 class TimeoutMonitor;
 class WebBluetoothServiceImpl;
 struct ContentSecurityPolicyHeader;
 struct ContextMenuParams;
 struct FileChooserParams;
 struct FrameOwnerProperties;
-struct GlobalRequestID;
 struct FileChooserParams;
-struct Referrer;
 struct ResourceResponse;
 
 class CONTENT_EXPORT RenderFrameHostImpl
     : public RenderFrameHost,
       NON_EXPORTED_BASE(public mojom::FrameHost),
       public BrowserAccessibilityDelegate,
       public SiteInstanceImpl::Observer,
       public NON_EXPORTED_BASE(
           service_manager::InterfaceFactory<media::mojom::InterfaceFactory>) {
  public:
@@ skipping 948 matching lines @@
       remote_associated_interfaces_;
   // NOTE: This must be the last member.
   base::WeakPtrFactory<RenderFrameHostImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderFrameHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_RENDER_FRAME_HOST_IMPL_H_