[DevTools] Cleanup DOMExtension.js.

third_party/WebKit/Source/devtools/front_end/timeline/TimelineEventOverview.js

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 470 matching lines @@
             this._frameToImagePromise.set(frame, imagePromise);
         }
         return imagePromise;
 
         /**
          * @param {?string} data
          * @return {!Promise<!HTMLImageElement>}
          */
         function createImage(data)
         {
+            var fulfill;
+            var promise = new Promise(f => fulfill = f);
+
             var image = /** @type {!HTMLImageElement} */ (createElement("img"));
             if (data)
                 image.src = "data:image/jpg;base64," + data;
-            return image.completePromise();
+            if (image.complete) {
+                fulfill(image);
+            } else {
+                image.addEventListener("load", () => fulfill(image));
+                image.addEventListener("error", () => fulfill(image));
+            }
+            return promise;
         }
     },
 
     /**
      * @param {number} imageWidth
      * @param {number} imageHeight
      */
     _drawFrames: function(imageWidth, imageHeight)
     {
         if (!imageWidth)
@@ skipping 304 matching lines @@
             counters[group] = this._quantDuration;
             this._callback(counters);
             interval -= this._quantDuration;
         }
         this._counters = [];
         this._counters[group] = interval;
         this._lastTime = time;
         this._remainder = this._quantDuration - interval;
     }
 }