Fix tests: "infix modifier required" and "operator modifier required" errors

compiler/testData/codegen/bytecodeText/componentEvaluatesOnlyOnce.kt

@@ -1,9 +1,9 @@
 class S(val a: String, val b: String) {
-  fun component1() : String = a
-  fun component2() : String = b
+  operator fun component1() : String = a
+  operator fun component2() : String = b
 }
 
-fun S.component3() = ((a + b) as java.lang.String).substring(2)
+operator fun S.component3() = ((a + b) as java.lang.String).substring(2)
 
 class Tester() {
   fun box() : String {
@@ -11,7 +11,7 @@ class Tester() {
     return o + k + ok + ok2
   }
 
-  fun S.component4() = ((a + b) as java.lang.String).substring(2)
+  operator fun S.component4() = ((a + b) as java.lang.String).substring(2)
 }
 
 fun box() = Tester().box()

compiler/testData/codegen/bytecodeText/stringOperations/infixPlus.kt

@@ -1,17 +0,0 @@
-class A() {
-
-    override fun toString(): String {
-        return "A"
-    }
-}
-
-
-fun box() : String {
-
-    val s = "1" plus "2" plus 3 plus 4L plus 5.0 plus 6F plus '7' plus A()
-
-    return "OK"
-}
-
-/*TODO:
-1 NEW java/lang/StringBuilder*/