Enable Wextra and Wno-unused-parameters in default cflags

services/prediction/dictionary_service.h

 // Copyright 2015 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 SERVICES_PREDICTION_DICTIONARY_SERVICE_H_
 #define SERVICES_PREDICTION_DICTIONARY_SERVICE_H_
 
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "mojo/services/prediction/interfaces/prediction.mojom.h"
@@ skipping 13 matching lines @@
   DictionaryService();
   ~DictionaryService();
 
   mojo::Array<mojo::String> GetDictionarySuggestion(
       PredictionInfoPtr prediction_info,
       latinime::ProximityInfo* proximity_info);
 
  private:
   void CreatDictFromEmbeddedDataIfNotExist(const std::string path);
 
-  latinime::Dictionary* const OpenDictionary(const std::string path,
-                                             const int start_offset,
-                                             const int size,
-                                             const bool is_updatable);
+  latinime::Dictionary* OpenDictionary(const std::string path,
+                                       const int start_offset,
+                                       const int size,
+                                       const bool is_updatable);
 
   latinime::PrevWordsInfo ProcessPrevWord(
       mojo::Array<PrevWordInfoPtr>& prev_words);
 
   int max_suggestion_size_;
   scoped_ptr<latinime::Dictionary> default_dictionary_;
   scoped_ptr<latinime::DicTraverseSession> default_session_;
 
   DISALLOW_COPY_AND_ASSIGN(DictionaryService);
 };
 
 }  // namespace prediction
 
 #endif  // SERVICES_PREDICTION_DICTIONARY_SERVICE_H_