fix SparkContextSchedulerCreationSuite test error

[scwf]

run test with the master branch with this command
sbt/sbt -Pyarn -Phadoop-2.3 -Dhadoop.version=2.3.0 -Pkinesis-as -Phive-thriftserver "test-only org.apache.spark.SparkContextSchedulerCreationSuite"

get this error:
[info] SparkContextSchedulerCreationSuite:
[info] - bad-master
[info] - local
[info] - local-*
[info] - local-n
[info] - local--n-failures
[info] - local-n-failures
[info] - bad-local-n
[info] - bad-local-n-failures
[info] - local-default-parallelism
[info] - simr
[info] - local-cluster
[info] - yarn-cluster
[info] - yarn-standalone
[info] - yarn-client
[info] - mesos fine-grained
[info] - mesos coarse-grained ** FAILED ***
[info] Spark home is not set; set it through the spark.home system property, the SPARK_HOME environment variable or the SparkContext constructor (SparkContextSchedulerCreationSuite.scala:158)

move "val sparkHome..." to createCommand method fix it.

[AmplabJenkins]

Can one of the admins verify this patch?

[vanzin]

LGTM.

[JoshRosen]

Jenkins, this is ok to test.

[scwf]

@JoshRosen，can you retest this pr？

[JoshRosen]

Jenkins, retest this please.

[SparkQA]

QA tests have started for PR 2052 at commit d9a8a60.

• This patch merges cleanly.

[SparkQA]

QA tests have finished for PR 2052 at commit d9a8a60.

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

[scwf]

@JoshRosen, retest this again, tests fails where this pr not changed (my locally tests is passed) , thanks~

[JoshRosen]

Jenkins, retest this please.

[SparkQA]

QA tests have started for PR 2052 at commit d9a8a60.

• This patch merges cleanly.

[SparkQA]

QA tests have finished for PR 2052 at commit d9a8a60.

• This patch passes unit tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
  • class BoundedFloat(float):
  • class JoinedRow2 extends Row
  • class JoinedRow3 extends Row
  • class JoinedRow4 extends Row
  • class JoinedRow5 extends Row
  • class GenericRow(protected[sql] val values: Array[Any]) extends Row
  • abstract class MutableValue extends Serializable
  • final class MutableInt extends MutableValue
  • final class MutableFloat extends MutableValue
  • final class MutableBoolean extends MutableValue
  • final class MutableDouble extends MutableValue
  • final class MutableShort extends MutableValue
  • final class MutableLong extends MutableValue
  • final class MutableByte extends MutableValue
  • final class MutableAny extends MutableValue
  • final class SpecificMutableRow(val values: Array[MutableValue]) extends MutableRow
  • case class CountDistinct(expressions: Seq[Expression]) extends PartialAggregate
  • case class CollectHashSet(expressions: Seq[Expression]) extends AggregateExpression
  • case class CollectHashSetFunction(
  • case class CombineSetsAndCount(inputSet: Expression) extends AggregateExpression
  • case class CombineSetsAndCountFunction(
  • case class CountDistinctFunction(
  • case class MaxOf(left: Expression, right: Expression) extends Expression
  • case class NewSet(elementType: DataType) extends LeafExpression
  • case class AddItemToSet(item: Expression, set: Expression) extends Expression
  • case class CombineSets(left: Expression, right: Expression) extends BinaryExpression
  • case class CountSet(child: Expression) extends UnaryExpression

[scwf]

@JoshRosen，this is good to go