[Web UI]Make decision order of Worker's WebUI port consistent with Master's

[WangTaoTheTonic]

The decision order of Worker's WebUI port is "--webui-port", SPARK_WORKER_WEBUI_POR, 8081(default), spark.worker.ui.port. But in Master, the order is "--webui-port", spark.master.ui.port, SPARK_MASTER_WEBUI_PORT and 8080(default).

So we change the order in Worker's to keep it consistent with Master.

[AmplabJenkins]

Can one of the admins verify this patch?

[andrewor14]

add to whitelist

[andrewor14]

LGTM if the tests pass. I guess we just never verified the order because no one was ever able to use the system properties to set the port until recently (a646a36)

[SparkQA]

QA tests have started for PR 1838. This patch merges cleanly.
View progress: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/18127/consoleFull

[SparkQA]

QA results for PR 1838:
- This patch FAILED unit tests.
- This patch merges cleanly
- This patch adds no public classes

For more information see test ouptut:
https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/18127/consoleFull

[WangTaoTheTonic]

Sorry for my carelessness. Now I fixed it.

[SparkQA]

QA tests have started for PR 1838. This patch merges cleanly.
View progress: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/18130/consoleFull

[SparkQA]

QA tests have started for PR 1838. This patch DID NOT merge cleanly!
View progress: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/18131/consoleFull

[SparkQA]

QA tests have started for PR 1838. This patch merges cleanly.
View progress: https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/18132/consoleFull

[SparkQA]

QA results for PR 1838:
- This patch PASSES unit tests.

For more information see test ouptut:
https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/18131/consoleFull

[SparkQA]

QA results for PR 1838:
- This patch PASSES unit tests.
- This patch merges cleanly
- This patch adds no public classes

For more information see test ouptut:
https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/18132/consoleFull

[SparkQA]

QA results for PR 1838:
- This patch PASSES unit tests.
- This patch merges cleanly
- This patch adds no public classes

For more information see test ouptut:
https://amplab.cs.berkeley.edu/jenkins/job/SparkPullRequestBuilder/18130/consoleFull

[andrewor14]

LGTM

[WangTaoTheTonic]

Could someone merge this? Thanks. @rxin

[rxin]

Thanks. I'm merging this in master.