@Override
                          public void onCompletion(Long result, Exception exception) {
                            asyncWritableChannel.close();
                          }
Test that an operation is completed with a specified {@link RouterErrorCode} when all gets on data chunks
in a multi-part blob return a specified {@link ServerErrorCode}
@param serverErrorCode The error code to be returned when fetching data chunks.
@param expectedErrorCode The operation's expected error code.
@throws Exception
ambry-router/src/test/java/com/github/ambry/router/GetBlobOperationTest.java