[SPARK-11129] [MESOS] Link Spark WebUI from Mesos WebUI

Mesos has a feature for linking to frameworks running on top of Mesos
from the Mesos WebUI. This commit enables Spark to make use of this
feature so one can directly visit the running Spark WebUIs from the
Mesos WebUI.

Author: ph <ph@plista.com>

Closes #9135 from philipphoffmann/SPARK-11129.

core/src/main/scala/org/apache/spark/scheduler/cluster/mesos/CoarseMesosSchedulerBackend.scala

@@ -127,7 +127,12 @@ private[spark] class CoarseMesosSchedulerBackend(
   override def start() {
     super.start()
     val driver = createSchedulerDriver(
-      master, CoarseMesosSchedulerBackend.this, sc.sparkUser, sc.appName, sc.conf)
+      master,
+      CoarseMesosSchedulerBackend.this,
+      sc.sparkUser,
+      sc.appName,
+      sc.conf,
+      sc.ui.map(_.appUIAddress))
     startScheduler(driver)
   }
 

core/src/main/scala/org/apache/spark/scheduler/cluster/mesos/MesosSchedulerBackend.scala

@@ -68,7 +68,12 @@ private[spark] class MesosSchedulerBackend(
   override def start() {
     classLoader = Thread.currentThread.getContextClassLoader
     val driver = createSchedulerDriver(
-      master, MesosSchedulerBackend.this, sc.sparkUser, sc.appName, sc.conf)
+      master,
+      MesosSchedulerBackend.this,
+      sc.sparkUser,
+      sc.appName,
+      sc.conf,
+      sc.ui.map(_.appUIAddress))
     startScheduler(driver)
   }