KT-925 step methods for integral ranges

compiler/testData/codegen/regressions/kt925.kt

@@ -0,0 +1,54 @@
+fun test1() : Boolean {
+    val r1 = 1..10
+    var s1 = 0
+    for(e in r1 step 2) {
+        s1 += e
+    }
+    return s1 == 25
+}
+
+fun test2() : Boolean {
+    val r1 = 1.byt..10.byt
+    var s1 = 0
+    for(e in r1 step 2) {
+        s1 += e
+    }
+    return s1 == 25
+}
+
+fun test3() : Boolean {
+    val r1 = 1.byt..10.lng
+    var s1 = 0.lng
+    for(e in r1 step 2) {
+        s1 += e
+    }
+    return s1 == 25.lng
+}
+
+fun test4() : Boolean {
+    val r1 = 1.byt..10.sht
+    var s1 = 0.sht
+    for(e in r1 step 2) {
+        s1 += e
+    }
+    return s1 == 25.sht
+}
+
+fun test5() : Boolean {
+    val r1 = 'a'..'h'
+    var s1 = 0
+    for(e in r1 step 2) {
+        s1 ++
+    }
+    return s1 == 4
+}
+
+fun box() : String {
+    if(test1().not()) return "test1 failed"
+    if(test2().not()) return "test2 failed"
+    if(test3().not()) return "test3 failed"
+    if(test4().not()) return "test4 failed"
+    if(test5().not()) return "test4 failed"
+
+    return "OK"
+}