Add version number to serialized DownloadAction data

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=169681768

library/core/src/test/java/com/google/android/exoplayer2/offline/ProgressiveDownloadActionTest.java

@@ -135,7 +135,8 @@ public class ProgressiveDownloadActionTest {
 
     ByteArrayInputStream in = new ByteArrayInputStream(out.toByteArray());
     DataInputStream input = new DataInputStream(in);
-    DownloadAction action2 = ProgressiveDownloadAction.DESERIALIZER.readFromStream(input);
+    DownloadAction action2 =
+        ProgressiveDownloadAction.DESERIALIZER.readFromStream(action1.getVersion(), input);
 
     assertThat(action2).isEqualTo(action1);
   }