Prevent "unexpected read attempt" illegal state exception

When using cronet data source, calling read after the end of input has
been read will trigger this.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=184667794

extensions/cronet/src/main/java/com/google/android/exoplayer2/ext/cronet/CronetDataSource.java

@@ -369,6 +369,7 @@ public class CronetDataSource extends UrlRequest.Callback implements HttpDataSou
         throw new HttpDataSourceException(exception, currentDataSpec,
             HttpDataSourceException.TYPE_READ);
       } else if (finished) {
+        bytesRemaining = 0;
         return C.RESULT_END_OF_INPUT;
       } else {
         // The operation didn't time out, fail or finish, and therefore data must have been read.