Don't restart the hang renderer timeout on messages ack'd from the compositor thread.

content/browser/renderer_host/input/mock_input_router_client.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_MOCK_INPUT_ROUTER_CLIENT_H_
 #define CONTENT_BROWSER_RENDERER_HOST_INPUT_MOCK_INPUT_ROUTER_CLIENT_H_
 
 #include <stddef.h>
 
 #include <memory>
@@ skipping 10 matching lines @@
  public:
   MockInputRouterClient();
   ~MockInputRouterClient() override;
 
   // InputRouterClient
   InputEventAckState FilterInputEvent(
       const blink::WebInputEvent& input_event,
       const ui::LatencyInfo& latency_info) override;
   void IncrementInFlightEventCount(
       blink::WebInputEvent::Type event_type) override;
-  void DecrementInFlightEventCount() override;
+  void DecrementInFlightEventCount(InputEventAckSource ack_source) override;
   void OnHasTouchEventHandlers(bool has_handlers) override;
   void DidFlush() override;
   void DidOverscroll(const ui::DidOverscrollParams& params) override;
   void DidStopFlinging() override;
   void ForwardGestureEventWithLatencyInfo(
       const blink::WebGestureEvent& gesture_event,
       const ui::LatencyInfo& latency_info) override;
 
   bool GetAndResetFilterEventCalled();
   size_t GetAndResetDidFlushCount();
@@ skipping 28 matching lines @@
   std::unique_ptr<InputEvent> last_filter_event_;
 
   size_t did_flush_called_count_;
 
   ui::DidOverscrollParams overscroll_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_MOCK_INPUT_ROUTER_CLIENT_H_