UMA metrics added for HID detection dialog.

chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.h

Index: chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.h
diff --git a/chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.h b/chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.h
index f8ff396eb75c64a4c388eed0bffcf0eb19d08ebb..c90c9e57612f08ab5f79fd627fdf643d40de8c79 100644
--- a/chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.h
+++ b/chrome/browser/ui/webui/chromeos/login/hid_detection_screen_handler.h
@@ -11,6 +11,7 @@
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
+#include "base/prefs/pref_registry_simple.h"
 #include "base/values.h"
 #include "chrome/browser/chromeos/device/input_service_proxy.h"
 #include "chrome/browser/chromeos/login/screens/hid_detection_screen_actor.h"
@@ -78,6 +79,9 @@ class HIDDetectionScreenHandler
   virtual void OnInputDeviceAdded(const InputDeviceInfo& info) OVERRIDE;
   virtual void OnInputDeviceRemoved(const std::string& id) OVERRIDE;
 
+  // Registers the preference for derelict state.
+  static void RegisterPrefs(PrefRegistrySimple* registry);
+
  private:
   void InitializeAdapter(scoped_refptr<device::BluetoothAdapter> adapter);
 
@@ -170,13 +174,32 @@ class HIDDetectionScreenHandler
 
   bool switch_on_adapter_when_ready_;
 
-  bool skip_screen_if_devices_present_;
+  bool first_time_screen_show_;
 
   base::WeakPtrFactory<HIDDetectionScreenHandler> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(HIDDetectionScreenHandler);
 };
 
+namespace hid {
+
+enum ContinueScenarioType {
+
+  // Only pointing device detected, user pressed 'Continue'.
+  POINTING_DEVICE_ONLY_DETECTED,
+
+  // Only keyboard detected, user pressed 'Continue'.
+  KEYBOARD_DEVICE_ONLY_DETECTED,
+
+  // All devices detected.
+  All_DEVICES_DETECTED,
+
+  // Must be last enum element.
+  CONTINUE_SCENARIO_TYPE_SIZE
+};
+
+}  // namespace hid
+
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_UI_WEBUI_CHROMEOS_LOGIN_HID_DETECTION_SCREEN_HANDLER_H_