Added test.

tests/cases/fourslash/codeFixAddForgottenDecoratorCall01.ts

@@ -0,0 +1,14 @@
+/// <reference path='fourslash.ts' />
+
+////declare function foo(): (...args: any[]) => void;
+////class C {
+////    [|@foo|]
+////    bar() {
+////
+////    }
+////}
+
+verify.codeFix({
+    description: "Call decorator expression.",
+    newRangeContent: `@foo()`
+});