Support 'windowed' intermediate call

idea/testData/debugger/sequence/exec/sequence/outs/windowed.out

@@ -2,9 +2,39 @@ LineBreakpoint created at Windowed.kt:5
 Run Java
 Connected to the target VM
 Windowed.kt:5
-Exception caught: junit.framework.AssertionFailedError: Unresolved reference: it, Unresolved reference: it
+intArrayOf(1, 1, 1, 1, 1, 1, 1).asSequence()
+.windowed(3, transform = { it.sum() })
+.count()
+windowed
+    before: 1,2,3,5,7,9,11
+    after: 4,6,8,10,12
+count
+    before: 4,6,8,10,12
+    after: nothing
+mappings for windowed
+  direct:
+    1 -> 4
+    2 -> 4,6
+    3 -> 4,6,8
+    5 -> 6,8,10
+    7 -> 8,10,12
+    9 -> nothing
+    11 -> nothing
+  reverse:
+    1,2,3 <- 4
+    2,3,5 <- 6
+    3,5,7 <- 8
+    5,7 <- 10
+    7 <- 12
+mappings for count
+  direct:
+    4 -> nothing
+    6 -> nothing
+    8 -> nothing
+    10 -> nothing
+    12 -> nothing
+  reverse:
+    empty
 Disconnected from the target VM
 
-WRONG!
-
 Process finished with exit code 0

idea/testData/debugger/sequence/exec/sequence/outs/windowedWithPartial.out

@@ -2,9 +2,37 @@ LineBreakpoint created at WindowedWithPartial.kt:5
 Run Java
 Connected to the target VM
 WindowedWithPartial.kt:5
-Exception caught: junit.framework.AssertionFailedError: Expected: <null> but was: CHAIN_CONSTRUCTION, Expected: <null> but was: CHAIN_CONSTRUCTION
+listOf(1, 1, 1, 1, 1).asSequence()
+.windowed(3, partialWindows = true, transform = { it.size })
+.count()
+windowed
+    before: 1,2,3,5,7
+    after: 4,6,8,9,10
+count
+    before: 4,6,8,9,10
+    after: nothing
+mappings for windowed
+  direct:
+    1 -> 4
+    2 -> 4,6
+    3 -> 4,6,8
+    5 -> 6,8,9
+    7 -> 8,9,10
+  reverse:
+    1,2,3 <- 4
+    2,3,5 <- 6
+    3,5,7 <- 8
+    5,7 <- 9
+    7 <- 10
+mappings for count
+  direct:
+    4 -> nothing
+    6 -> nothing
+    8 -> nothing
+    9 -> nothing
+    10 -> nothing
+  reverse:
+    empty
 Disconnected from the target VM
 
-WRONG!
-
 Process finished with exit code 0

idea/testData/debugger/sequence/exec/sequence/src/misc/Windowed.kt

@@ -2,5 +2,5 @@ package misc
 
 fun main(args: Array<String>) {
   // Breakpoint!
-  intArrayOf(1, 1, 1, 1, 1, 1, 1).asSequence().windowed(3) { it.sum() }.count()
+  intArrayOf(1, 1, 1, 1, 1, 1, 1).asSequence().windowed(3, transform = { it.sum() }) .count()
 }

idea/testData/debugger/sequence/exec/sequence/src/misc/WindowedWithPartial.kt

@@ -2,5 +2,5 @@ package misc
 
 fun main(args: Array<String>) {
   // Breakpoint!
-  listOf(1, 1, 1, 1, 1).windowed(3, partialWindows = true) { it.size }.count()
+  listOf(1, 1, 1, 1, 1).asSequence().windowed(3, partialWindows = true, transform = { it.size }).count()
 }

idea/testData/debugger/sequence/exec/sequence/src/sort/SortedBy.kt

@@ -1,4 +1,3 @@
-// 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 sort
 
 fun main(args: Array<String>) {
@@ -6,4 +5,4 @@ fun main(args: Array<String>) {
   arrayOf(Person("Bob", 42), Person("Alice", 27)).asSequence().sortedBy { it.age }.count()
 }
 
-internal data class Person(val name: String, val age: Int)
+data class Person(val name: String, val age: Int)