Make SsMediaSource.Builder a factory for SsMediaSources

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=178380856

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

@@ -388,10 +388,9 @@ import java.util.ArrayList;
     Uri uri = Uri.parse(sample.uri);
     switch (sample.mimeType) {
       case DemoUtil.MIME_TYPE_SS:
-        return SsMediaSource.Builder
-            .forManifestUri(uri, DATA_SOURCE_FACTORY,
-                new DefaultSsChunkSource.Factory(DATA_SOURCE_FACTORY))
-            .build();
+        return new SsMediaSource.Factory(
+                new DefaultSsChunkSource.Factory(DATA_SOURCE_FACTORY), DATA_SOURCE_FACTORY)
+            .createMediaSource(uri);
       case DemoUtil.MIME_TYPE_DASH:
         return new DashMediaSource.Factory(
                 new DefaultDashChunkSource.Factory(DATA_SOURCE_FACTORY), DATA_SOURCE_FACTORY)

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

@@ -365,11 +365,10 @@ public class PlayerActivity extends Activity implements OnClickListener,
         : Util.inferContentType("." + overrideExtension);
     switch (type) {
       case C.TYPE_SS:
-        return SsMediaSource.Builder
-            .forManifestUri(uri, buildDataSourceFactory(false),
-                new DefaultSsChunkSource.Factory(mediaDataSourceFactory))
-            .setEventListener(mainHandler, eventLogger)
-            .build();
+        return new SsMediaSource.Factory(
+                new DefaultSsChunkSource.Factory(mediaDataSourceFactory),
+                buildDataSourceFactory(false))
+            .createMediaSource(uri, mainHandler, eventLogger);
       case C.TYPE_DASH:
         return new DashMediaSource.Factory(
                 new DefaultDashChunkSource.Factory(mediaDataSourceFactory),