Introduces a search term extraction mechanism working for arbitrary search providers.

chrome/browser/webdata/keyword_table.h

Index: chrome/browser/webdata/keyword_table.h
diff --git a/chrome/browser/webdata/keyword_table.h b/chrome/browser/webdata/keyword_table.h
index 1293a4ba040fb18d2eeb2f1755a7059550e23b05..6004deb96fefbb1141fc4f81675da65663ef6d6f 100644
--- a/chrome/browser/webdata/keyword_table.h
+++ b/chrome/browser/webdata/keyword_table.h
@@ -51,6 +51,8 @@ class Statement;
 //                          in version 38.
 //   sync_guid              See TemplateURLData::sync_guid. This was added in
 //                          version 39.
+//   alternate_urls         See TemplateURLData::alternate_urls_. This was added
+//                          in version 47.
 //
 // keywords_backup          The full copy of the |keywords| table. Added in
 //                          version 43. Must be in sync with |keywords|
@@ -141,6 +143,7 @@ class KeywordTable : public WebDatabaseTable {
   bool MigrateToVersion39AddSyncGUIDColumn();
   bool MigrateToVersion44AddDefaultSearchProviderBackup();
   bool MigrateToVersion45RemoveLogoIDAndAutogenerateColumns();
+  bool MigrateToVersion47AddAlternateUrlsColumn();
 
  private:
   FRIEND_TEST_ALL_PREFIXES(KeywordTableTest, DefaultSearchProviderBackup);
@@ -194,7 +197,7 @@ class KeywordTable : public WebDatabaseTable {
   bool UpdateDefaultSearchProviderIDBackup(TemplateURLID* id);
 
   // Migrates table |name| (which should be either "keywords" or
-  // "keywords_backup" from version 44 to version 45.
+  // "keywords_backup") from version 44 to version 45.
   bool MigrateKeywordsTableForVersion45(const std::string& name);
 
   // Whether the backup was overwritten during migration.