Fix isLive and seekRange for native HLS

By fixing the definitions of isLive and seekRange for native HLS and
other src= playbacks, the UI for live streams with native HLS is now
working correctly on Safari.

Issue #382
Issue #997

Change-Id: I3d4f49ebe31a543c75f8607e7a194095ef198c0a

lib/player.js

@@ -2510,9 +2510,16 @@ shaka.Player.prototype.getManifestUri = function() {
  * @export
  */
 shaka.Player.prototype.isLive = function() {
-  return this.loadMode_ == shaka.Player.LoadMode.MEDIA_SOURCE ?
-         this.manifest_.presentationTimeline.isLive() :
-         false;
+  if (this.manifest_) {
+    return this.manifest_.presentationTimeline.isLive();
+  }
+
+  // For native HLS, the duration for live streams seems to be Infinity.
+  if (this.video_ && this.video_.src) {
+    return this.video_.duration == Infinity;
+  }
+
+  return false;
 };
 
 
@@ -2571,23 +2578,28 @@ shaka.Player.prototype.isAudioOnly = function() {
  * @export
  */
 shaka.Player.prototype.seekRange = function() {
-  // If we have loaded content with src=, we assume that the whole presentation
-  // is seekable. For mp4, this is always the case. For HLS, this may not always
-  // be the case, but there is no way for us to get this information.
-  if (this.loadMode_ == shaka.Player.LoadMode.SRC_EQUALS) {
-    return {'start': 0, 'end': this.video_.duration};
-  }
+  if (this.manifest_) {
+    const timeline = this.manifest_.presentationTimeline;
 
-  if (this.loadMode_ != shaka.Player.LoadMode.MEDIA_SOURCE) {
-    return {'start': 0, 'end': 0};
+    return {
+      'start': timeline.getSeekRangeStart(),
+      'end': timeline.getSeekRangeEnd(),
+    };
   }
 
-  const timeline = this.manifest_.presentationTimeline;
+  // If we have loaded content with src=, we ask the video element for its
+  // seekable range.  This covers both plain mp4s and native HLS playbacks.
+  if (this.video_ && this.video_.src) {
+    const seekable = this.video_.seekable;
+    if (seekable.length) {
+      return {
+        'start': seekable.start(0),
+        'end': seekable.end(seekable.length - 1),
+      };
+    }
+  }
 
-  return {
-    'start': timeline.getSeekRangeStart(),
-    'end': timeline.getSeekRangeEnd(),
-  };
+  return {'start': 0, 'end': 0};
 };