Update moe equivalence

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=196024195

extensions/okhttp/src/main/java/com/google/android/exoplayer2/ext/okhttp/OkHttpDataSource.java

@@ -170,7 +170,7 @@ public class OkHttpDataSource implements HttpDataSource {
 
     // Check for a valid response code.
     if (!response.isSuccessful()) {
-      Map<String, List<String>> headers = request.headers().toMultimap();
+      Map<String, List<String>> headers = response.headers().toMultimap();
       closeConnectionQuietly();
       InvalidResponseCodeException exception = new InvalidResponseCodeException(
           responseCode, headers, dataSpec);