Added link feature

Author: sarutak

core/src/main/resources/org/apache/spark/ui/static/timeline-view.js

@@ -177,6 +177,10 @@ function drawTaskAssignmentTimeline(groupArray, eventObjArray, minLaunchTime, zo
         return taskIdx;
       };
 
+      $(this).click(function() {
+        window.location.href = "#task-" + getTaskIdx(this);
+      });
+
       $(this).hover(
         function() {
           var id = getTaskIdx(this);

core/src/main/scala/org/apache/spark/ui/jobs/StagePage.scala

@@ -535,7 +535,7 @@ private[ui] class StagePage(parent: StagesTab) extends WebUIPage("stage") {
       val executorComputingTime = metricsOpt.map(_.executorRunTime).getOrElse(0L) -
         shuffleReadTime - shuffleWriteTime
       val executorComputingTimeProportion =
-        (executorComputingTime / totalExecutionTime * 100).toLong
+        (executorComputingTime.toDouble / totalExecutionTime * 100).toLong
       val serializationTime = metricsOpt.map(_.resultSerializationTime).getOrElse(0L)
       val serializationTimeProportion =
         (serializationTime.toDouble / totalExecutionTime * 100).toLong
@@ -739,7 +739,7 @@ private[ui] class StagePage(parent: StagesTab) extends WebUIPage("stage") {
       val diskBytesSpilledSortable = maybeDiskBytesSpilled.map(_.toString).getOrElse("")
       val diskBytesSpilledReadable = maybeDiskBytesSpilled.map(Utils.bytesToString).getOrElse("")
 
-      <tr>
+      <tr id={"task-" + info.index}>
         <td>{info.index}</td>
         <td>{info.taskId}</td>
         <td sorttable_customkey={info.attempt.toString}>{