fix(Web): frame事件列表为空

web/dist/vap.js

@@ -1923,7 +1923,7 @@
 
         var timePoint = info && info.mediaTime >= 0 ? info.mediaTime : this.video.currentTime;
         var frame = Math.round(timePoint * this.options.fps) + this.options.offset;
-        var frameCbs = this.events['frame'];
+        var frameCbs = this.events['frame'] || [];
         frameCbs.forEach(function (cb) {
           cb(frame + 1, timePoint);
         });

web/package.json

@@ -1,6 +1,6 @@
 {
   "name": "video-animation-player",
-  "version": "0.2.7",
+  "version": "0.2.8",
   "description": "webgl动画特效组件",
   "main": "dist/vap.js",
   "scripts": {

web/src/webgl-render-vap.ts

@@ -286,7 +286,7 @@ export default class WebglRenderVap extends VapVideo {
   drawFrame(_, info) {
     const timePoint = (info && info.mediaTime >= 0) ? info.mediaTime : this.video.currentTime
     const frame = Math.round(timePoint * this.options.fps) + this.options.offset;
-    const frameCbs = this.events['frame']
+    const frameCbs = this.events['frame'] || []
     frameCbs.forEach(cb => {
       cb(frame + 1, timePoint)
     })