fix(copy): support copying MediaStream object

use MediaStream clone method to clone mediastream object

Closes angular#16055

Author: m-amr

src/Angular.js

@@ -1005,6 +1005,9 @@ function copy(source, destination, maxDepth) {
 
       case '[object Blob]':
         return new source.constructor([source], {type: source.type});
+
+      case '[object MediaStream]':
+        return source.clone();
     }
 
     if (isFunction(source.cloneNode)) {

test/AngularSpec.js

@@ -603,6 +603,13 @@ describe('angular', function() {
       /* eslint-enable */
     });
 
+    it('should copy media stream objects', function() {
+      window.getUserMedia({video:true, audio:false}, function(stream) {
+        var streamCopy = copy(stream);
+        expect(streamCopy).toEqual(stream);
+      });
+    });
+
     it('should copy source until reaching a given max depth', function() {
       var source = {a1: 1, b1: {b2: {b3: 1}}, c1: [1, {c2: 1}], d1: {d2: 1}};
       var dest;