电脑上面测试时候可以保存视频和相册，在手机端无法保存怎么回事呢？
proto__: Object __defineGetter__: function() __defineSetter__: function() __lookupGetter__: function() __lookupSetter__: function() __proto__: null constructor: function() hasOwnProperty: function() isPrototypeOf: function() nv_constructor: "Object" nv_toString: function() propertyIsEnumerable: function() toLocaleString: function() toString: function() valueOf: function() __proto__: null
