in tool/icons/update_icons.dart [92:120]
void generateDart(
List<Icon> icons, String filename, String prefix, String import) {
final StringBuffer buf = StringBuffer();
buf.writeln('''
// Generated file - do not edit.
import 'package:flutter/$import.dart';
class IconTuple {
final IconData data;
final String name;
final Key smallKey = new UniqueKey();
final Key largeKey = new UniqueKey();
IconTuple(this.data, this.name);
}
final List<IconTuple> icons = [''');
for (final Icon icon in icons) {
buf.writeln(' new IconTuple($prefix.${icon.name}, \'${icon.name}\'),');
}
buf.writeln('];');
File(filename).writeAsStringSync(buf.toString());
print('wrote $filename');
}