Add tests for mapping operations

idea/testData/debugger/sequence/exec/sequence/src/map/Map.kt

@@ -0,0 +1,7 @@
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package map
+
+fun main(args: Array<String>) {
+  // Breakpoint!
+  doubleArrayOf(1.0, 2.0).asSequence().map { it * it }.contains(3.0)
+}

idea/testData/debugger/sequence/exec/sequence/src/map/MapIndexed.kt

@@ -0,0 +1,6 @@
+package map
+
+fun main(args: Array<String>) {
+  // Breakpoint!
+  intArrayOf(1, 2, 3, 4).asSequence().mapIndexed { ix, _ -> ix }.count()
+}

idea/testData/debugger/sequence/exec/sequence/src/map/MapNotNull.kt

@@ -0,0 +1,6 @@
+package map
+
+fun main(args: Array<String>) {
+  // Breakpoint!
+  val lst = listOf(1, 2, null, 3).asSequence().mapNotNull { if (it != null && it % 2 == 1) it else null }.toList()
+}

idea/testData/debugger/sequence/exec/sequence/src/map/WithIndex.kt

@@ -0,0 +1,7 @@
+// Copyright 2000-2017 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package map
+
+fun main(args: Array<String>) {
+  // Breakpoint!
+  intArrayOf(1, 2, 3).asSequence().withIndex().forEach {}
+}