[SPARK-8657] [YARN] Simplify method addResource() and get the correct fs from destPath.

[litao-buptsse]

[SPARK-8657] [YARN] Simplify method addResource() and get the correct fs from destPath.

JIRA Link: https://issues.apache.org/jira/browse/SPARK-8657

[srowen]

OK to test

[SparkQA]

Test build #967 has finished for PR 7053 at commit 75b457e.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
  • case class Sha2(left: Expression, right: Expression)

[litao-buptsse]

Some unit tests failed. I will review my PR code again.

[litao-buptsse]

@srowen I think maybe the first fs param in addResource() is needed, especially it's useful when doing unit test. I see the ClientDistributedCacheManagerSuite usually pass a mock fs to the addResource(). So I think to keep the first fs param might be better, although it's sometimes redundant.

ClientDistributedCacheManagerSuite unit tests: https://github.com/apache/spark/blob/master/yarn/src/test/scala/org/apache/spark/deploy/yarn/ClientDistributedCacheManagerSuite.scala

My failed unit tests: https://amplab.cs.berkeley.edu/jenkins/job/NewSparkPullRequestBuilder/967/testReport/org.apache.spark.deploy.yarn/

[srowen]

OK to test

[SparkQA]

Test build #976 has finished for PR 7053 at commit 75b457e.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.