Make HlsMediaSource.Builder a factory for HlsMediaSources

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=178384204

demos/cast/src/main/java/com/google/android/exoplayer2/castdemo/PlayerManager.java

@@ -396,9 +396,7 @@ import java.util.ArrayList;
                 new DefaultDashChunkSource.Factory(DATA_SOURCE_FACTORY), DATA_SOURCE_FACTORY)
             .createMediaSource(uri);
       case DemoUtil.MIME_TYPE_HLS:
-        return HlsMediaSource.Builder
-            .forDataSource(uri, DATA_SOURCE_FACTORY)
-            .build();
+        return new HlsMediaSource.Factory(DATA_SOURCE_FACTORY).createMediaSource(uri);
       case DemoUtil.MIME_TYPE_VIDEO_MP4:
         return new ExtractorMediaSource.Builder(uri, DATA_SOURCE_FACTORY).build();
       default: {

demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

@@ -375,10 +375,8 @@ public class PlayerActivity extends Activity implements OnClickListener,
                 buildDataSourceFactory(false))
             .createMediaSource(uri, mainHandler, eventLogger);
       case C.TYPE_HLS:
-        return HlsMediaSource.Builder
-            .forDataSource(uri, mediaDataSourceFactory)
-            .setEventListener(mainHandler, eventLogger)
-            .build();
+        return new HlsMediaSource.Factory(mediaDataSourceFactory)
+            .createMediaSource(uri, mainHandler, eventLogger);
       case C.TYPE_OTHER:
         return new ExtractorMediaSource.Builder(uri, mediaDataSourceFactory)
             .setEventListener(mainHandler, eventLogger)