Generalize migration code in WebDatabase.

chrome/browser/webdata/web_apps_table.cc

Index: chrome/browser/webdata/web_apps_table.cc
diff --git a/chrome/browser/webdata/web_apps_table.cc b/chrome/browser/webdata/web_apps_table.cc
index a503925af73947d2eb9962a8e74627d0bed42449..927b934c6e1322912591a03fca6c8c3a9dbdc0f9 100644
--- a/chrome/browser/webdata/web_apps_table.cc
+++ b/chrome/browser/webdata/web_apps_table.cc
@@ -19,6 +19,12 @@ bool WebAppsTable::IsSyncable() {
   return true;
 }
 
+bool WebAppsTable::MigrateToVersion(int version,
+                                    const std::string& app_locale,
+                                    bool* update_compatible_version) {
+  return true;
+}
+
 bool WebAppsTable::InitWebAppIconsTable() {
   if (!db_->DoesTableExist("web_app_icons")) {
     if (!db_->Execute("CREATE TABLE web_app_icons ("