KT-935 resolved call used on +=

compiler/testData/codegen/regressions/kt935.kt

@@ -0,0 +1,30 @@
+package bottles
+
+fun box() : String {
+    var bottles = 10
+    while (bottles > 0) {
+        print(bottlesOfBeer(bottles) + " on the wall, ")
+        println(bottlesOfBeer(bottles) + ".")
+        print("Take one down, pass it around, ")
+        if (--bottles == 0) {
+            println("no more bottles of beer on the wall.")
+        }
+        else {
+            println(bottlesOfBeer(bottles) + " on the wall.")
+        }
+    }
+    return "OK"
+}
+
+fun bottlesOfBeer(count : Int) :  String {
+    val result = StringBuilder()
+    result += count
+    result += if (count > 1) " bottles of beer" else " bottle of beer"
+    return result.toString() ?: ""
+}
+
+// An excerpt from the standard library
+fun print(message : String) { System.out?.print(message) }
+fun println(message : String) { System.out?.println(message) }
+fun StringBuilder.plusAssign(o : Any) { append(o) }
+val <T> Array<T>.isEmpty : Boolean get() = size == 0