[SPARK-7838] [STREAMING] Set scope for kinesis stream

Author: Tathagata Das <tathagata.das1565@gmail.com>

Closes #6369 from tdas/SPARK-7838 and squashes the following commits:

87d1c7f [Tathagata Das] Addressed comment
37775d8 [Tathagata Das] set scope for kinesis stream

extras/kinesis-asl/src/main/scala/org/apache/spark/streaming/kinesis/KinesisUtils.scala

@@ -63,9 +63,12 @@ object KinesisUtils {
       checkpointInterval: Duration,
       storageLevel: StorageLevel
     ): ReceiverInputDStream[Array[Byte]] = {
-    ssc.receiverStream(
-      new KinesisReceiver(kinesisAppName, streamName, endpointUrl, validateRegion(regionName),
-        initialPositionInStream, checkpointInterval, storageLevel, None))
+    // Setting scope to override receiver stream's scope of "receiver stream"
+    ssc.withNamedScope("kinesis stream") {
+      ssc.receiverStream(
+        new KinesisReceiver(kinesisAppName, streamName, endpointUrl, validateRegion(regionName),
+          initialPositionInStream, checkpointInterval, storageLevel, None))
+    }
   }
 
   /**

streaming/src/main/scala/org/apache/spark/streaming/StreamingContext.scala

@@ -262,7 +262,7 @@ class StreamingContext private[streaming] (
    *
    * Note: Return statements are NOT allowed in the given body.
    */
-  private def withNamedScope[U](name: String)(body: => U): U = {
+  private[streaming] def withNamedScope[U](name: String)(body: => U): U = {
     RDDOperationScope.withScope(sc, name, allowNesting = false, ignoreParent = false)(body)
   }