Forbidden old invokeExtension convention.

compiler/testData/diagnostics/tests/FreeFunctionCalledAsExtension.kt

@@ -1,5 +1,5 @@
 fun foo(a: (String) -> Unit) {
-    "".<!FREE_FUNCTION_CALLED_AS_EXTENSION!>a<!>()
+    "".<!INVOKE_EXTENSION_ON_NOT_EXTENSION_FUNCTION!>a<!>()
 }
 
 
@@ -9,5 +9,5 @@ interface A : (String) -> Unit {}
 fun foo(a: @Extension A) {
     // @Extension annotation on an unrelated type shouldn't have any effect on this diagnostic.
     // Only kotlin.Function{n} type annotated with @Extension should
-    "".<!FREE_FUNCTION_CALLED_AS_EXTENSION!>a<!>()
-}
+    "".<!INVOKE_EXTENSION_ON_NOT_EXTENSION_FUNCTION!>a<!>()
+}