1676 [local_auth] Use post instead of postDelayed (cla: yes)

1677 [firebase_dynamic_links] Fix Android crashing when a headless plugin register this plugin. (bugfix, cla: yes, flutterfire)

1678 [firebase_remote_config] Add missing template type parameter to invokeMethod calls. Bump minimum Flutter version to 1.5.0. Replace invokeMethod with invokeMapMethod wherever necessary. (cla: yes)

1679 [firebase_storage]Add missing template type parameter to invokeMethod calls. Bump minimum Flutter version to 1.5.0. Replace invokeMethod with invokeMapMethod wherever necessary. (cla: yes)

1680 [google_map_flutter] Add missing template type parameter to invokeMethod calls. Bump minimum Flutter version to 1.5.0. Replace invokeMethod with invokeMapMethod wherever necessary. (cla: yes)