Use correctElementType to determine array element type for withIndex

Rather unkind "gotcha" in ASM API.

 #KT-23900 Fixed Target versions 1.2.50

compiler/testData/codegen/box/controlStructures/forInArrayWithIndex/forInArrayOfObjectArrayWithIndex.kt

@@ -0,0 +1,12 @@
+// WITH_RUNTIME
+
+fun box(): String {
+    val arr = Array(4) { arrayOf("x$it") }
+
+    var s = ""
+    for ((i, sarr) in arr.withIndex()) {
+        s += "$i:${sarr.toList()}"
+    }
+
+    return if (s != "0:[x0]1:[x1]2:[x2]3:[x3]") "Fail: '$s'" else "OK"
+}

compiler/testData/codegen/box/controlStructures/forInArrayWithIndex/forInArrayOfPrimArrayWithIndex.kt

@@ -0,0 +1,14 @@
+// WITH_RUNTIME
+
+fun box(): String {
+    // [[0], [1], [2], [3]]
+    val arr = Array(4) { intArrayOf(it) }
+
+    var s = 0
+    for ((i, iarr) in arr.withIndex()) {
+        s += i*iarr[0]
+    }
+
+    // 0 + 1 + 4 + 9 = 14
+    return if (s != 14) "Fail: $s" else "OK"
+}