Fixed some Scala style errors.

Author: zhangjiajin

mllib/src/main/scala/org/apache/spark/mllib/fpm/LocalPrefixSpan.scala

@@ -65,7 +65,7 @@ private[fpm] object LocalPrefixSpan extends Logging with Serializable {
       if (element.length > 1 && flag == 1) {
         element.take(element.length - 1) ++ originalSequence
       } else if (element.length == 1 && flag == 1) {
-        val firstPosition =  originalSequence.indexOf(-1)
+        val firstPosition = originalSequence.indexOf( -1 )
         if (firstPosition != -1) {
           originalSequence.drop(firstPosition + 1)
         } else {

mllib/src/main/scala/org/apache/spark/mllib/fpm/PrefixSpan.scala

@@ -103,7 +103,7 @@ class PrefixSpan private (
 
   private def sortSequences(sequences: RDD[Array[Int]]): RDD[Array[Int]] = {
     sequences.map { sequence =>
-      val sortedArray: ArrayBuffer[Int]  = ArrayBuffer()
+      val sortedArray: ArrayBuffer[Int] = ArrayBuffer()
       var currentIndex = -1
       var nextIndex = 0
       while (nextIndex != -1) {

mllib/src/test/scala/org/apache/spark/mllib/fpm/PrefixSpanSuite.scala

@@ -175,7 +175,8 @@ class PrefixSpanSuite extends SparkFunSuite with MLlibTestSparkContext {
       "f,c,b:2")
     val intExpectedValue = expectedValue4
       .map(_.split(":"))
-      .map(x => (x.apply(0).split(",").flatMap(-1 +: _.toArray.map(coder)).drop(1), x.apply(1).toLong))
+      .map { x =>
+      (x.apply(0).split(",").flatMap(-1 +: _.toArray.map(coder)).drop(1), x.apply(1).toLong) }
     assert(compareResult(intExpectedValue, result4.collect()))
   }
 }