make methods private

src/core/core.controller.js

@@ -966,7 +966,7 @@ helpers.extend(Chart.prototype, /** @lends Chart */ {
 		}
 
 		if (mode === 'dataset') {
-			this.getDatasetMeta(elements[0]._datasetIndex).controller[prefix + 'DatasetHoverStyle']();
+			this.getDatasetMeta(elements[0]._datasetIndex).controller['_' + prefix + 'DatasetHoverStyle']();
 		}
 	},
 

src/core/core.datasetController.js

@@ -470,15 +470,21 @@ helpers.extend(DatasetController.prototype, {
 		model.borderWidth = resolve([custom.hoverBorderWidth, dataset.hoverBorderWidth, model.borderWidth], undefined, index);
 	},
 
-	removeDatasetHoverStyle: function() {
+	/**
+	 * @private
+	 */
+	_removeDatasetHoverStyle: function() {
 		var element = this.getMeta().dataset;
 
 		if (element) {
 			this.removeHoverStyle(element);
 		}
 	},
 
-	setDatasetHoverStyle: function() {
+	/**
+	 * @private
+	 */
+	_setDatasetHoverStyle: function() {
 		var element = this.getMeta().dataset;
 		var prev = {};
 		var i, ilen, key, keys, hoverOptions, model;