content: Cleanup class/struct forward declarations

content/browser/renderer_host/input/input_router.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_RENDERER_HOST_INPUT_INPUT_ROUTER_H_
 #define CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_H_
 
 #include "content/browser/renderer_host/event_with_latency_info.h"
 #include "content/common/input/input_event_ack_state.h"
 #include "content/public/browser/native_web_keyboard_event.h"
 #include "ipc/ipc_listener.h"
 #include "third_party/WebKit/public/web/WebInputEvent.h"
 
 namespace content {
 
-class InputRouterClient;
-
 // The InputRouter allows the embedder to customize how input events are
 // sent to the renderer, and how responses are dispatched to the browser.
 // While the router should respect the relative order in which events are
 // received, it is free to customize when those events are dispatched.
 class InputRouter : public IPC::Listener {
  public:
   ~InputRouter() override {}
 
   // Send and take ownership of the the given InputMsg_*. This should be used
   // only for event types not associated with a WebInputEvent.  Returns true on
@@ skipping 32 matching lines @@
   virtual void SetDeviceScaleFactor(float device_scale_factor) = 0;
 
   // Sets the frame tree node id of associated frame, used when tracing
   // input event latencies to relate events to their target frames.
   virtual void SetFrameTreeNodeId(int frameTreeNodeId) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_H_