[SPARK-2108] Mark SparkContext methods that return block information …

…as developer API's

Author: Prashant Sharma <prashant.s@imaginea.com>

Closes #1047 from ScrapCodes/SPARK-2108/mark-as-dev-api and squashes the following commits:

073ee34 [Prashant Sharma] [SPARK-2108] Mark SparkContext methods that return block information as developer API's

core/src/main/scala/org/apache/spark/SparkContext.scala

@@ -823,9 +823,11 @@ class SparkContext(config: SparkConf) extends Logging {
   }
 
   /**
+   * :: DeveloperApi ::
    * Return information about what RDDs are cached, if they are in mem or on disk, how much space
    * they take, etc.
    */
+  @DeveloperApi
   def getRDDStorageInfo: Array[RDDInfo] = {
     StorageUtils.rddInfoFromStorageStatus(getExecutorStorageStatus, this)
   }
@@ -837,8 +839,10 @@ class SparkContext(config: SparkConf) extends Logging {
   def getPersistentRDDs: Map[Int, RDD[_]] = persistentRdds.toMap
 
   /**
+   * :: DeveloperApi ::
    * Return information about blocks stored in all of the slaves
    */
+  @DeveloperApi
   def getExecutorStorageStatus: Array[StorageStatus] = {
     env.blockManager.master.getStorageStatus
   }