Revert changes in python

Author: andrewor14

python/pyspark/conf.py

@@ -30,7 +30,7 @@
 u'local'
 >>> sc.appName
 u'My app'
->>> sc.sparkHome is not None
+>>> sc.sparkHome is None
 True
 
 >>> conf = SparkConf(loadDefaults=False)

python/pyspark/context.py

@@ -126,6 +126,8 @@ def _do_init(self, master, appName, sparkHome, pyFiles, environment, batchSize,
             self._conf.setMaster(master)
         if appName:
             self._conf.setAppName(appName)
+        if sparkHome:
+            self._conf.setSparkHome(sparkHome)
         if environment:
             for key, value in environment.iteritems():
                 self._conf.setExecutorEnv(key, value)
@@ -142,7 +144,7 @@ def _do_init(self, master, appName, sparkHome, pyFiles, environment, batchSize,
         # the classpath or an external config file
         self.master = self._conf.get("spark.master")
         self.appName = self._conf.get("spark.app.name")
-        self.sparkHome = os.environ.get("SPARK_HOME")
+        self.sparkHome = self._conf.get("spark.home", None)
         for (k, v) in self._conf.getAll():
             if k.startswith("spark.executorEnv."):
                 varName = k[len("spark.executorEnv."):]