Disable test while Roman is looking into it to fix the build.

gottesmm · gottesmm · commit 3b7a5c6dd8b6 · 2016-07-26T23:07:18.000-07:00
rdar://17028332
diff --git a/validation-test/stdlib/String.swift b/validation-test/stdlib/String.swift
@@ -1,5 +1,6 @@
 // RUN: %target-run-simple-swift
 // REQUIRES: executable_test
+// REQUIRES: rdar17028332
 
 // XFAIL: interpret
 
