mus: Add PointerWatcher for passively observing mouse and touch events

components/mus/demo/mus_demo.h

 // Copyright 2016 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 COMPONENTS_MUS_DEMO_MUS_DEMO_H_
 #define COMPONENTS_MUS_DEMO_MUS_DEMO_H_
 
 #include <map>
 #include <memory>
 #include <string>
@@ skipping 31 matching lines @@
   // shell::ShellClient:
   void Initialize(shell::Connector* connector,
                   const shell::Identity& identity,
                   uint32_t id) override;
   bool AcceptConnection(shell::Connection* connection) override;
 
   // WindowTreeDelegate:
   void OnEmbed(mus::Window* root) override;
   void OnUnembed(mus::Window* root) override;
   void OnConnectionLost(mus::WindowTreeConnection* connection) override;
+  void OnEventObserved(const ui::Event& event) override;
 
   // WindowManagerDelegate:
   void SetWindowManagerClient(mus::WindowManagerClient* client) override;
   bool OnWmSetBounds(mus::Window* window, gfx::Rect* bounds) override;
   bool OnWmSetProperty(
       mus::Window* window,
       const std::string& name,
       std::unique_ptr<std::vector<uint8_t>>* new_data) override;
   mus::Window* OnWmCreateTopLevelWindow(
       std::map<std::string, std::vector<uint8_t>>* properties) override;
@@ skipping 21 matching lines @@
 
   // Current rotation angle for drawing.
   double angle_ = 0.0;
 
   DISALLOW_COPY_AND_ASSIGN(MusDemo);
 };
 
 }  // namespace mus_demo
 
 #endif  // COMPONENTS_MUS_DEMO_MUS_DEMO_H_