Change the name of findOldestFiles() to findOldFiles()

Author: Kelvin Chu

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

@@ -196,7 +196,7 @@ private[spark] class Worker(
       // Spin up a separate thread (in a future) to do the dir cleanup; don't tie up worker actor
       val cleanupFuture = concurrent.future {
         logInfo("Cleaning up oldest application directories in " + workDir + " ...")
-        Utils.findOldestFiles(workDir, APP_DATA_RETENTION_SECS)
+        Utils.findOldFiles(workDir, APP_DATA_RETENTION_SECS)
              .foreach(Utils.deleteRecursively(_))
       }
       cleanupFuture onFailure {

core/src/main/scala/org/apache/spark/util/Utils.scala

@@ -541,7 +541,7 @@ private[spark] object Utils extends Logging {
    * @param dir  must be the path to a directory, or IllegalArgumentException is thrown
    * @param cutoff measured in seconds. Files older than this are returned.
    */
-  def findOldestFiles(dir: File, cutoff: Long): Seq[File] = {
+  def findOldFiles(dir: File, cutoff: Long): Seq[File] = {
     val currentTimeSecs = System.currentTimeMillis / 1000
     if (dir.isDirectory) {
       val files = listFilesSafely(dir)

core/src/test/scala/org/apache/spark/util/UtilsSuite.scala

@@ -155,7 +155,7 @@ class UtilsSuite extends FunSuite {
     assert(Utils.getIteratorSize(iterator) === 5L)
   }
 
-  test("findOldestFiles") {
+  test("findOldFiles") {
     // create some temporary directories and files
     val parent: File = Utils.createTempDir()
     val child1: File = Utils.createTempDir(parent.getCanonicalPath) // The parent directory has two child directories