Don't persist and sync omnibox extension keywords.

components/search_engines/keyword_table.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 "components/search_engines/keyword_table.h"
 
 #include <set>
 
 #include "base/json/json_reader.h"
 #include "base/json/json_writer.h"
@@ skipping 217 matching lines @@
       return MigrateToVersion48RemoveKeywordsBackup();
     case 49:
       *update_compatible_version = true;
       return MigrateToVersion49AddSearchTermsReplacementKeyColumn();
     case 52:
       *update_compatible_version = true;
       return MigrateToVersion52AddImageSearchAndPOSTSupport();
     case 53:
       *update_compatible_version = true;
       return MigrateToVersion53AddNewTabURLColumn();
+    case 59:
+      *update_compatible_version = true;
+      return MigrateToVersion59RemoveExtensionKeywords();
   }
 
   return true;
 }
 
 bool KeywordTable::PerformOperations(const Operations& operations) {
   sql::Transaction transaction(db_);
   if (!transaction.Begin())
     return false;
 
@@ skipping 196 matching lines @@
       db_->Execute("ALTER TABLE keywords ADD COLUMN image_url_post_params "
                    "VARCHAR DEFAULT ''") &&
       transaction.Commit();
 }
 
 bool KeywordTable::MigrateToVersion53AddNewTabURLColumn() {
   return db_->Execute("ALTER TABLE keywords ADD COLUMN new_tab_url "
                       "VARCHAR DEFAULT ''");
 }
 
+bool KeywordTable::MigrateToVersion59RemoveExtensionKeywords() {
+  return db_->Execute("DELETE FROM keywords "
+                      "WHERE url LIKE 'chrome-extension://%'");
+}
+
 // static
 bool KeywordTable::GetKeywordDataFromStatement(const sql::Statement& s,
                                                TemplateURLData* data) {
   DCHECK(data);
 
   data->short_name = s.ColumnString16(1);
   data->SetKeyword(s.ColumnString16(2));
   // Due to past bugs, we might have persisted entries with empty URLs.  Avoid
   // reading these out.  (GetKeywords() will delete these entries on return.)
   // NOTE: This code should only be needed as long as we might be reading such
@@ skipping 174 matching lines @@
     }
   }
 
   // Replace the old table with the new one.
   sql = "DROP TABLE " + name;
   if (!db_->Execute(sql.c_str()))
     return false;
   sql = "ALTER TABLE keywords_temp RENAME TO " + name;
   return db_->Execute(sql.c_str());
 }