Updates are aborted when seeking

Buffered will not be present in segment info when a segment processing is aborted due to seeking. Make sure bufferedAdditions_ does not error or add incorrect timeline information to the segment in that case.

@@ -228,6 +228,12 @@ videojs.Hls.bufferedAdditions_ = function(original, update) {
   var result = [], edges = [],
       i, inOriginalRanges;
 
+  // if original or update are falsey, return an empty list of
+  // additions
+  if (!original || !update) {
+    return result;
+  }
+
   // create a sorted array of time range start and end times
   for (i = 0; i < original.length; i++) {
     edges.push({ original: true, start: original.start(i) });

@@ -2553,4 +2553,11 @@ test('detects time range edges added by updates', function() {
   ], 'detected a non-contiguous addition');
 });
 
+test('treats null buffered ranges as no addition', function() {
+  var edges = videojs.Hls.bufferedAdditions_(null,
+                                             videojs.createTimeRange([[0, 11]]));
+
+  equal(edges.length, 0, 'no additions');
+});
+
 })(window, window.videojs);