Add simplified Dash and Ss media source factory constructors.

As the manifest and media data sources can be the same now, we can provide
a simplified constructor with just one data source factory.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=205658046

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

@@ -36,9 +36,7 @@ import com.google.android.exoplayer2.source.ConcatenatingMediaSource;
 import com.google.android.exoplayer2.source.ExtractorMediaSource;
 import com.google.android.exoplayer2.source.MediaSource;
 import com.google.android.exoplayer2.source.dash.DashMediaSource;
-import com.google.android.exoplayer2.source.dash.DefaultDashChunkSource;
 import com.google.android.exoplayer2.source.hls.HlsMediaSource;
-import com.google.android.exoplayer2.source.smoothstreaming.DefaultSsChunkSource;
 import com.google.android.exoplayer2.source.smoothstreaming.SsMediaSource;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
 import com.google.android.exoplayer2.ui.PlayerControlView;
@@ -392,13 +390,9 @@ import java.util.ArrayList;
     Uri uri = Uri.parse(sample.uri);
     switch (sample.mimeType) {
       case DemoUtil.MIME_TYPE_SS:
-        return new SsMediaSource.Factory(
-                new DefaultSsChunkSource.Factory(DATA_SOURCE_FACTORY), DATA_SOURCE_FACTORY)
-            .createMediaSource(uri);
+        return new SsMediaSource.Factory(DATA_SOURCE_FACTORY).createMediaSource(uri);
       case DemoUtil.MIME_TYPE_DASH:
-        return new DashMediaSource.Factory(
-                new DefaultDashChunkSource.Factory(DATA_SOURCE_FACTORY), DATA_SOURCE_FACTORY)
-            .createMediaSource(uri);
+        return new DashMediaSource.Factory(DATA_SOURCE_FACTORY).createMediaSource(uri);
       case DemoUtil.MIME_TYPE_HLS:
         return new HlsMediaSource.Factory(DATA_SOURCE_FACTORY).createMediaSource(uri);
       case DemoUtil.MIME_TYPE_VIDEO_MP4:

demos/ima/src/main/java/com/google/android/exoplayer2/imademo/PlayerManager.java

@@ -27,9 +27,7 @@ import com.google.android.exoplayer2.source.ExtractorMediaSource;
 import com.google.android.exoplayer2.source.MediaSource;
 import com.google.android.exoplayer2.source.ads.AdsMediaSource;
 import com.google.android.exoplayer2.source.dash.DashMediaSource;
-import com.google.android.exoplayer2.source.dash.DefaultDashChunkSource;
 import com.google.android.exoplayer2.source.hls.HlsMediaSource;
-import com.google.android.exoplayer2.source.smoothstreaming.DefaultSsChunkSource;
 import com.google.android.exoplayer2.source.smoothstreaming.SsMediaSource;
 import com.google.android.exoplayer2.trackselection.AdaptiveTrackSelection;
 import com.google.android.exoplayer2.trackselection.DefaultTrackSelector;
@@ -123,13 +121,9 @@ import com.google.android.exoplayer2.util.Util;
     @ContentType int type = Util.inferContentType(uri);
     switch (type) {
       case C.TYPE_DASH:
-        return new DashMediaSource.Factory(
-                new DefaultDashChunkSource.Factory(dataSourceFactory), dataSourceFactory)
-            .createMediaSource(uri);
+        return new DashMediaSource.Factory(dataSourceFactory).createMediaSource(uri);
       case C.TYPE_SS:
-        return new SsMediaSource.Factory(
-                new DefaultSsChunkSource.Factory(dataSourceFactory), dataSourceFactory)
-            .createMediaSource(uri);
+        return new SsMediaSource.Factory(dataSourceFactory).createMediaSource(uri);
       case C.TYPE_HLS:
         return new HlsMediaSource.Factory(dataSourceFactory).createMediaSource(uri);
       case C.TYPE_OTHER:

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

@@ -58,11 +58,9 @@ import com.google.android.exoplayer2.source.TrackGroupArray;
 import com.google.android.exoplayer2.source.ads.AdsLoader;
 import com.google.android.exoplayer2.source.ads.AdsMediaSource;
 import com.google.android.exoplayer2.source.dash.DashMediaSource;
-import com.google.android.exoplayer2.source.dash.DefaultDashChunkSource;
 import com.google.android.exoplayer2.source.dash.manifest.DashManifestParser;
 import com.google.android.exoplayer2.source.hls.HlsMediaSource;
 import com.google.android.exoplayer2.source.hls.playlist.HlsPlaylistParser;
-import com.google.android.exoplayer2.source.smoothstreaming.DefaultSsChunkSource;
 import com.google.android.exoplayer2.source.smoothstreaming.SsMediaSource;
 import com.google.android.exoplayer2.source.smoothstreaming.manifest.SsManifestParser;
 import com.google.android.exoplayer2.trackselection.AdaptiveTrackSelection;
@@ -438,14 +436,12 @@ public class PlayerActivity extends Activity
     @ContentType int type = Util.inferContentType(uri, overrideExtension);
     switch (type) {
       case C.TYPE_DASH:
-        return new DashMediaSource.Factory(
-                new DefaultDashChunkSource.Factory(dataSourceFactory), dataSourceFactory)
+        return new DashMediaSource.Factory(dataSourceFactory)
             .setManifestParser(
                 new FilteringManifestParser<>(new DashManifestParser(), getOfflineStreamKeys(uri)))
             .createMediaSource(uri);
       case C.TYPE_SS:
-        return new SsMediaSource.Factory(
-                new DefaultSsChunkSource.Factory(dataSourceFactory), dataSourceFactory)
+        return new SsMediaSource.Factory(dataSourceFactory)
             .setManifestParser(
                 new FilteringManifestParser<>(new SsManifestParser(), getOfflineStreamKeys(uri)))
             .createMediaSource(uri);

library/dash/src/main/java/com/google/android/exoplayer2/source/dash/DashMediaSource.java

@@ -86,6 +86,16 @@ public final class DashMediaSource extends BaseMediaSource {
     /**
      * Creates a new factory for {@link DashMediaSource}s.
      *
+     * @param dataSourceFactory A factory for {@link DataSource} instances that will be used to load
+     *     manifest and media data.
+     */
+    public Factory(DataSource.Factory dataSourceFactory) {
+      this(new DefaultDashChunkSource.Factory(dataSourceFactory), dataSourceFactory);
+    }
+
+    /**
+     * Creates a new factory for {@link DashMediaSource}s.
+     *
      * @param chunkSourceFactory A factory for {@link DashChunkSource} instances.
      * @param manifestDataSourceFactory A factory for {@link DataSource} instances that will be used
      *     to load (and refresh) the manifest. May be {@code null} if the factory will only ever be

library/smoothstreaming/src/main/java/com/google/android/exoplayer2/source/smoothstreaming/SsMediaSource.java

@@ -73,6 +73,16 @@ public final class SsMediaSource extends BaseMediaSource
     /**
      * Creates a new factory for {@link SsMediaSource}s.
      *
+     * @param dataSourceFactory A factory for {@link DataSource} instances that will be used to load
+     *     manifest and media data.
+     */
+    public Factory(DataSource.Factory dataSourceFactory) {
+      this(new DefaultSsChunkSource.Factory(dataSourceFactory), dataSourceFactory);
+    }
+
+    /**
+     * Creates a new factory for {@link SsMediaSource}s.
+     *
      * @param chunkSourceFactory A factory for {@link SsChunkSource} instances.
      * @param manifestDataSourceFactory A factory for {@link DataSource} instances that will be used
      *     to load (and refresh) the manifest. May be {@code null} if the factory will only ever be