'Loads the manifest (for either hosted or packaged) and updates
Version.supported_locales for the current version or latest version if
latest=True.'

def update_supported_locales(self, latest=False, manifest=None):

    version = (self.versions.latest() if latest else self.current_version)
    if (not manifest):
        file_ = version.all_files[0]
        manifest = self.get_manifest_json(file_)
    updated = False
    supported_locales = ','.join(get_supported_locales(manifest))
    if (version.supported_locales != supported_locales):
        updated = True
        version.update(supported_locales=supported_locales, _signal=False)
    return updated
