Returns the display type that this display requires.
This can be used for filtering views plugins. E.g. if a plugin category of 'foo' is specified, only plugins with no 'types' declared or 'types' containing 'foo'. If you have a type of bar, this plugin will not be used. This is applicable for style, row, access, cache, and exposed_form plugins.
string The required display type. Defaults to 'normal'.
protected function getType() {
return 'normal';
}