Fix test testMsgTriggeredRebalance

[huizhilu]

Issues

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Fixes #1116

Description

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Unit test testMsgTriggeredRebalance() consistently fails, because we allow ignoring pending messages and sending ST messages when current state equals pending msg's to state. We should change the test condition a bit to allow messages number >= 1.

Two changes for the test:

1. verify messages on each live instance are not purged. here
2. This is the change to pass the test, allowing messages size >= 1. here

This PR also formats the file TestRebalancePipeline.java

Tests

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Changed testMsgTriggeredRebalance

• The following is the result of the "mvn test" command on the appropriate module:

Only fix the test so just run and pass the single test.

END testMsgTriggeredRebalance at Tue Jun 23 01:54:12 PDT 2020, took: 7861ms.
Shut down zookeeper at port 2183 in thread main

===============================================
Default Suite
Total tests run: 1, Failures: 0, Skips: 0
===============================================

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[huizhilu]

This is the change to pass the test, allowing messages size >= 1

[huizhilu]

Change 1: verify messages on each live instance are not purged.