FileRef implementation = createFile("testImplementation",
"<gxp:implements interface='testInterface' />",
"<gxp:param name='foo' content-type='text/plain' />");
compileFiles(iface, implementation);
assertAlert(new ParamTypeMismatchError(pos(2,1), "foo", "text/html", "text/plain"));
assertNoUnexpectedAlerts();
}