Merge pull request #3171 from joseph2rs/widget_image_fix_revoke_object_url

fix: [Widget Image] Remove oldurl string check since it's always a string and prevent the ObjectURL cleaning resulting in a memory leak.

Author: jasongrout

packages/controls/src/widget_audio.ts

@@ -62,7 +62,7 @@ export class AudioView extends DOMWidgetView {
     // Clean up the old objectURL
     const oldurl = this.el.src;
     this.el.src = url;
-    if (oldurl && typeof oldurl !== 'string') {
+    if (oldurl) {
       URL.revokeObjectURL(oldurl);
     }
 

packages/controls/src/widget_image.ts

@@ -62,9 +62,10 @@ export class ImageView extends DOMWidgetView {
     // Clean up the old objectURL
     const oldurl = this.el.src;
     this.el.src = url;
-    if (oldurl && typeof oldurl !== 'string') {
+    if (oldurl) {
       URL.revokeObjectURL(oldurl);
     }
+
     const width = this.model.get('width');
     if (width !== undefined && width.length > 0) {
       this.el.setAttribute('width', width);

packages/controls/src/widget_video.ts

@@ -65,7 +65,7 @@ export class VideoView extends DOMWidgetView {
     // Clean up the old objectURL
     const oldurl = this.el.src;
     this.el.src = url;
-    if (oldurl && typeof oldurl !== 'string') {
+    if (oldurl) {
       URL.revokeObjectURL(oldurl);
     }