[Hotword] Add error message display back in. Add error messages for NaCl. Add metrics for errors.

chrome/browser/search/hotword_service.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 CHROME_BROWSER_SEARCH_HOTWORD_SERVICE_H_
 #define CHROME_BROWSER_SEARCH_HOTWORD_SERVICE_H_
 
 #include "base/basictypes.h"
 #include "base/prefs/pref_change_registrar.h"
 #include "components/keyed_service/core/keyed_service.h"
@@ skipping 41 matching lines @@
   virtual bool IsServiceAvailable();
 
   // Determine if hotwording is allowed in this profile based on field trials
   // and language.
   virtual bool IsHotwordAllowed();
 
   // Checks if the user has opted into audio logging. Returns true if the user
   // is opted in, false otherwise..
   bool IsOptedIntoAudioLogging();
 
-  // Used in the case of an error with the current hotword extension. Tries
-  // to reload the extension or in the case of failure, tries to re-download it.
-  // Returns true upon successful attempt at reload or if the extension has
-  // already loaded successfully by some other means.
-  virtual bool RetryHotwordExtension();
-
   // Control the state of the hotword extension.
   void EnableHotwordExtension(ExtensionService* extension_service);
   void DisableHotwordExtension(ExtensionService* extension_service);
 
   // Handles enabling/disabling the hotword extension when the user
   // turns it off via the settings menu.
   void OnHotwordSearchEnabledChanged(const std::string& pref_name);
 
   // Called to handle the hotword session from |client|.
   void RequestHotwordSession(HotwordClient* client);
   void StopHotwordSession(HotwordClient* client);
   HotwordClient* client() { return client_; }
 
+  // Returns the current error message id. A value of 0 indicates
+  // no error.
+  int error_message() { return error_message_; }
+
  private:
   Profile* profile_;
 
   PrefChangeRegistrar pref_registrar_;
 
   content::NotificationRegistrar registrar_;
 
   HotwordClient* client_;
+  int error_message_;
 
   DISALLOW_COPY_AND_ASSIGN(HotwordService);
 };
 
 #endif  // CHROME_BROWSER_SEARCH_HOTWORD_SERVICE_H_