Refactor Udev device support in Ozone and add a DRM hotplug monitor

ui/events/ozone/evdev/device_manager_evdev.h

 // Copyright 2014 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 UI_EVENTS_OZONE_EVDEV_DEVICE_MANAGER_EVDEV_H_
 #define UI_EVENTS_OZONE_EVDEV_DEVICE_MANAGER_EVDEV_H_
 
 #include "base/callback.h"
 #include "base/compiler_specific.h"
 #include "base/files/file_path.h"
 #include "base/memory/scoped_ptr.h"
+#include "ui/events/events_export.h"
 
 namespace ui {
 
 typedef base::Callback<void(const base::FilePath& file_path)>
     EvdevDeviceCallback;
 
 // Interface for scanning & monitoring input devices.
 class DeviceManagerEvdev {
  public:
   virtual ~DeviceManagerEvdev();
 
   // Enumerate devices & start watching for changes.
   // Must be balanced by a call to Stop().
   virtual void ScanAndStartMonitoring(
       const EvdevDeviceCallback& device_added,
       const EvdevDeviceCallback& device_removed) = 0;
 
   // Stop watching for device changes.
   virtual void Stop() = 0;
 };
 
 // Create simple DeviceManagerEvdev that scans /dev/input manually.
-scoped_ptr<DeviceManagerEvdev> CreateDeviceManagerManual();
+EVENTS_EXPORT scoped_ptr<DeviceManagerEvdev> CreateDeviceManagerManual();
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_OZONE_EVDEV_DEVICE_MANAGER_EVDEV_H_