Remove old default search preferences.

chrome/browser/prefs/tracked/pref_hash_browsertest.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 <memory>
 #include <string>
 
 #include "base/base_switches.h"
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 1214 matching lines @@
           "id" : 1
         }, {
           "keyword" : "badkeyword2",
           "name" : "badname2",
           "search_url" : "http://bad_default_engine2/search?q=dirty_user_query",
           "encoding" : "utf-8",
           "id" : 2
         }
       ]
     })";
-    static constexpr char default_search_provider[] = R"(
-    {
-      "default_search_provider" : {
-        "keyword" : "badkeyword",
-        "name" : "badname",
-        "search_url" : "http://bad_default_engine/search?q=dirty_user_query"
-      }
-    })";
 
     // Try to override default search in all three of available preferences.
     auto attack1 = base::DictionaryValue::From(
         base::JSONReader::Read(default_search_provider_data));
     auto attack2 = base::DictionaryValue::From(
         base::JSONReader::Read(search_provider_overrides));
-    auto attack3 = base::DictionaryValue::From(
-        base::JSONReader::Read(default_search_provider));
     unprotected_preferences->MergeDictionary(attack1.get());
     unprotected_preferences->MergeDictionary(attack2.get());
-    unprotected_preferences->MergeDictionary(attack3.get());
     if (protected_preferences) {
       // Override here, too.
       protected_preferences->MergeDictionary(attack1.get());
       protected_preferences->MergeDictionary(attack2.get());
-      protected_preferences->MergeDictionary(attack3.get());
     }
   }
 
   void VerifyReactionToPrefAttack() override {
     DefaultSearchManager default_search_manager(
         profile()->GetPrefs(), DefaultSearchManager::ObserverCallback());
     DefaultSearchManager::Source dse_source =
         static_cast<DefaultSearchManager::Source>(-1);
 
     const TemplateURLData* current_dse =
@@ skipping 14 matching lines @@
       EXPECT_EQ(DefaultSearchManager::FROM_FALLBACK, dse_source);
       EXPECT_NE(current_dse->keyword(), base::UTF8ToUTF16("badkeyword"));
       EXPECT_NE(current_dse->short_name(), base::UTF8ToUTF16("badname"));
       EXPECT_NE(current_dse->url(),
                 "http://bad_default_engine/search?q=dirty_user_query");
     }
   }
 };
 
 PREF_HASH_BROWSER_TEST(PrefHashBrowserTestDefaultSearch, SearchProtected);