Standardize usage of virtual/override/final specifiers.

content/renderer/manifest/manifest_parser_unittest.cc

 // 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.
 
 #include "content/renderer/manifest/manifest_parser.h"
 
 #include "base/strings/string_util.h"
 #include "content/public/common/manifest.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace content {
 
 class ManifestParserTest : public testing::Test  {
  protected:
   ManifestParserTest() {}
-  virtual ~ManifestParserTest() {}
+  ~ManifestParserTest() override {}
 
   Manifest ParseManifest(const base::StringPiece& json,
                          const GURL& document_url = default_document_url,
                          const GURL& manifest_url = default_manifest_url) {
     return ManifestParser::Parse(json, document_url, manifest_url);
   }
 
   static const GURL default_document_url;
   static const GURL default_manifest_url;
 
@@ skipping 571 matching lines @@
     Manifest manifest = ParseManifest("{ \"gcm_sender_id\": {} }");
     EXPECT_TRUE(manifest.gcm_sender_id.is_null());
   }
   {
     Manifest manifest = ParseManifest("{ \"gcm_sender_id\": 42 }");
     EXPECT_TRUE(manifest.gcm_sender_id.is_null());
   }
 }
 
 } // namespace content