Clear pending events upon main frame navigation

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 "base/basictypes.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 {}
 
-  // Should be called only in response to |SetNeedsFlush| requests made via
-  // the |InputRouterClient|.
-  virtual void Flush() = 0;
-
   // 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
   // success and false otherwise.
   virtual bool SendInput(scoped_ptr<IPC::Message> message) = 0;
 
   // WebInputEvents
   virtual void SendMouseEvent(
       const MouseEventWithLatencyInfo& mouse_event) = 0;
   virtual void SendWheelEvent(
       const MouseWheelEventWithLatencyInfo& wheel_event) = 0;
   virtual void SendKeyboardEvent(
       const NativeWebKeyboardEvent& key_event,
       const ui::LatencyInfo& latency_info,
       bool is_shortcut) = 0;
   virtual void SendGestureEvent(
       const GestureEventWithLatencyInfo& gesture_event) = 0;
   virtual void SendTouchEvent(
       const TouchEventWithLatencyInfo& touch_event) = 0;
 
+  // Request a notification from the router (through its client) when it becomes
+  // empty after dispatching all current and pending events. Note that this is
+  // not a strict flush marker, as the router will wait until *all* input has
+  // been dispatched, potentially including future input.
+  virtual void RequestFlushedNotification() = 0;
+
   // Returns the oldest queued or in-flight keyboard event sent to the router.
   virtual const NativeWebKeyboardEvent* GetLastKeyboardEvent() const = 0;
 
   // Returns |true| if the caller should immediately forward touch events to the
   // router.  When |false|, the caller can forego sending touch events, and
   // instead consume them directly.
   virtual bool ShouldForwardTouchEvent() const = 0;
 
   // Allow the router to make more informed input handling decisions based on
   // the current view.
   enum ViewFlags {
     VIEW_FLAGS_NONE   = 0,
     FIXED_PAGE_SCALE  = 1 << 0,
     MOBILE_VIEWPORT   = 1 << 1
   };
   virtual void OnViewUpdated(int view_flags) = 0;
 
   virtual bool HasPendingEvents() const = 0;
 };
 
 }  // namespace content
 
 #endif // CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_H_