Remove the link on the application summary page

Author: nblintao

core/src/main/scala/org/apache/spark/deploy/DeployMessage.scala

@@ -177,7 +177,6 @@ private[deploy] object DeployMessages {
       host: String,
       port: Int,
       restPort: Option[Int],
-      webUiUrl: String,
       workers: Array[WorkerInfo],
       activeApps: Array[ApplicationInfo],
       completedApps: Array[ApplicationInfo],

core/src/main/scala/org/apache/spark/deploy/master/Master.scala

@@ -471,7 +471,7 @@ private[deploy] class Master(
 
     case RequestMasterState =>
       context.reply(MasterStateResponse(
-        address.host, address.port, restServerBoundPort, masterWebUiUrl,
+        address.host, address.port, restServerBoundPort,
         workers.toArray, apps.toArray, completedApps.toArray,
         drivers.toArray, completedDrivers.toArray, state))
 

core/src/main/scala/org/apache/spark/deploy/master/ui/ApplicationPage.scala

@@ -35,7 +35,6 @@ private[ui] class ApplicationPage(parent: MasterWebUI) extends WebUIPage("app")
   def render(request: HttpServletRequest): Seq[Node] = {
     val appId = request.getParameter("appId")
     val state = master.askWithRetry[MasterStateResponse](RequestMasterState)
-    val masterWebUiUrl = state.webUiUrl
     val app = state.activeApps.find(_.id == appId)
       .getOrElse(state.completedApps.find(_.id == appId).orNull)
     if (app == null) {
@@ -82,7 +81,6 @@ private[ui] class ApplicationPage(parent: MasterWebUI) extends WebUIPage("app")
               }
             }
           </ul>
-          <p><a href={masterWebUiUrl}>Back to Master</a></p>
         </div>
       </div>
 

core/src/test/scala/org/apache/spark/deploy/JsonProtocolSuite.scala

@@ -69,7 +69,7 @@ class JsonProtocolSuite extends SparkFunSuite with JsonTestUtils {
     val activeDrivers = Array(createDriverInfo())
     val completedDrivers = Array(createDriverInfo())
     val stateResponse = new MasterStateResponse(
-      "host", 8080, None, "host:port", workers, activeApps, completedApps,
+      "host", 8080, None, workers, activeApps, completedApps,
       activeDrivers, completedDrivers, RecoveryState.ALIVE)
     val output = JsonProtocol.writeMasterState(stateResponse)
     assertValidJson(output)