actually stop the webcam, i.e. all tracks of the media stream when stopping video

HISTORY.md

@@ -79,6 +79,7 @@
 
 ### 2019-05-07
 * Blocks, Objects, Threads, Video: optimized video motion detection
+* Objects: actually stop the webcam, i.e. all tracks of the media stream when stopping video
 
 ### 2019-05-06
 * Blocks, Objects, Threads, Video: New video motion detection feature by Josep Ferràndiz i Farré, under construction

src/objects.js

@@ -7324,6 +7324,9 @@ StageMorph.prototype.startVideo = function(isFlipped) {
 
 StageMorph.prototype.stopVideo = function() {
     if (this.videoElement) {
+        this.videoElement.stream.getTracks().forEach(
+            function (track) {track.stop(); }
+        );
         this.videoElement.remove();
         this.videoElement = null;
         this.videoMotion = null;