+
+ // Upgrade from schema version 1 to schema version 2.
+ case 1:
+ {
+ // Add the User Agent column.
+ domainsDatabase.exec("ALTER TABLE " + DOMAINS_TABLE + " ADD COLUMN " + USER_AGENT + " TEXT DEFAULT '" + UserAgentHelper::SYSTEM_DEFAULT_DATABASE + "'");
+
+ // Fallthrough to the next case.
+ [[fallthrough]];
+ }
+
+ // Upgrade from schema version 2 to schema version 3.
+ case 2:
+ {
+ // Add the Zoom Factor columns.
+ domainsDatabase.exec("ALTER TABLE " + DOMAINS_TABLE + " ADD COLUMN " + ZOOM_FACTOR + " INTEGER DEFAULT 0");
+ domainsDatabase.exec("ALTER TABLE " + DOMAINS_TABLE + " ADD COLUMN " + CUSTOM_ZOOM_FACTOR + " REAL DEFAULT 1.0");
+
+ // Fallthrough to the next case.
+ [[fallthrough]];
+ }
+
+ // Upgrade from schema version 3 to schema version 4.
+ case 3:
+ // Add the DOM Storage column.
+ domainsDatabase.exec("ALTER TABLE " + DOMAINS_TABLE + " ADD COLUMN " + DOM_STORAGE + " INTEGER DEFAULT 0");