Code review feedback.

Author: rxin

core/src/main/scala/org/apache/spark/deploy/worker/DriverRunner.scala

@@ -33,8 +33,6 @@ import org.apache.spark.deploy.master.DriverState
 import org.apache.spark.deploy.master.DriverState.DriverState
 import org.apache.spark.util.{Clock, SystemClock}
 
-import scala.collection.mutable
-
 /**
  * Manages the execution of one driver, including automatically restarting the driver on failure.
  * This is currently only used in standalone cluster deploy mode.
@@ -178,7 +176,7 @@ private[deploy] class DriverRunner(
   }
 
   def runCommandWithRetry(
-      command: ProcessBuilderLike, initialize: Process => Unit, supervise: Boolean) {
+      command: ProcessBuilderLike, initialize: Process => Unit, supervise: Boolean): Unit = {
     // Time to wait between submission retries.
     var waitSeconds = 1
     // A run of this many seconds resets the exponential back-off.

core/src/main/scala/org/apache/spark/metrics/MetricsSystem.scala

@@ -20,11 +20,10 @@ package org.apache.spark.metrics
 import java.util.Properties
 import java.util.concurrent.TimeUnit
 
-import org.eclipse.jetty.servlet.ServletContextHandler
-
 import scala.collection.mutable
 
 import com.codahale.metrics.{Metric, MetricFilter, MetricRegistry}
+import org.eclipse.jetty.servlet.ServletContextHandler
 
 import org.apache.spark.{Logging, SecurityManager, SparkConf}
 import org.apache.spark.metrics.sink.{MetricsServlet, Sink}

scalastyle-config.xml

@@ -75,7 +75,7 @@
    <parameter name="regex"><![CDATA[^[a-z][A-Za-z]*$]]></parameter>
   </parameters>
  </check>
- <check level="error" class="org.scalastyle.scalariform.EqualsHashCodeChecker" enabled="false"></check>
+ <check level="error" class="org.scalastyle.scalariform.EqualsHashCodeChecker" enabled="true"></check>
  <!-- <check level="error" class="org.scalastyle.scalariform.IllegalImportsChecker" enabled="true"> -->
  <!--  <parameters> -->
  <!--   <parameter name="illegalImports"><![CDATA[sun._,java.awt._]]></parameter> -->
@@ -137,9 +137,9 @@
  <!--   <parameter name="maxMethods"><![CDATA[30]]></parameter> -->
  <!--  </parameters> -->
  <!-- </check> -->
- <!-- <check level="error" class="org.scalastyle.scalariform.PublicMethodsHaveTypeChecker" enabled="true"></check> -->
+ <check level="error" class="org.scalastyle.scalariform.PublicMethodsHaveTypeChecker" enabled="true"></check>
  <check level="error" class="org.scalastyle.file.NewLineAtEofChecker" enabled="true"></check>
  <check level="error" class="org.scalastyle.file.NoNewLineAtEofChecker" enabled="false"></check>
- <check level="error" class="org.apache.spark.scalastyle.NonASCIICharacterChecker" enabled="true"></check>
+ <check level="error" class="org.scalastyle.scalariform.NonASCIICharacterChecker" enabled="true"></check>
  <check level="error" class="org.scalastyle.scalariform.SpaceAfterCommentStartChecker" enabled="true"></check>
 </scalastyle>