function initConfig(config) {
		config = config || {};

		// Do NOT use configMerge() for the data object because this method merges arrays
		// and so would change references to labels and datasets, preventing data updates.
		var data = config.data = config.data || {};
		data.datasets = data.datasets || [];
		data.labels = data.labels || [];

		config.options = helpers.configMerge(
			defaults.global,
			defaults[config.type],
			config.options || {});

		return config;
	}
Initializes the given config with global and chart default values.