[ISSUE #465] topic should be added to topicList instead of clu…

[RongtongJin]

…ster name and broker name

What is the purpose of the change

Fix bug issues#465, topic should be added to topicList instead of cluster name and broker name

Brief changelog

In RouteInfoManager.getSystemTopicList() method,
1.Remove the code which adds cluster name and broker name to topicList.
2.Add topic name to topicList.

Verifying this change

Verified this change by running RouteInfoManagerTest.testGetSystemTopicList() unit test

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[coveralls]

Coverage increased (+0.02%) to 42.383% when pulling 80a98be on RongtongJin:master into a220364 on apache:master.

[vongosling]

@RongtongJin Could you please to change your target commit to develop instead of master. Another, make some unit-test for the polish :-)

[RongtongJin]

I think my understanding of systemTopicList is incorrect.
At the beginning, I thought that getSystemTopicList means getting all the topic names, then I read the code carefully yesterday and found RouteInfoManager.getAllTopicList() has done this. I traced the call chain of getSystemToplicList and found MQClientAPIImpl.getSystemTopicList() is the last method called, so RouteManagerInfo.getSystemTopicList() never be called? ? ?
At the same time, I found some systemTopic will be added in rocketmq.broker.topic.TopicConfigManager#TopicConfigManager() when the BrokerController is initialized, including the broker name and cluster name. So systemTopicList should include broker name and cluster name. The original code is correct.