[regexp] character class for desugaring cannot be part of RegExpText.

test/mjsunit/harmony/unicode-regexp-ignore-case.js

Index: test/mjsunit/harmony/unicode-regexp-ignore-case.js
diff --git a/test/mjsunit/harmony/unicode-regexp-ignore-case.js b/test/mjsunit/harmony/unicode-regexp-ignore-case.js
index 7e930745bf4cc6a5fa292d116bcd541bc90af03d..8382eeafed25a03dcc206a47a1a231395da35fbb 100644
--- a/test/mjsunit/harmony/unicode-regexp-ignore-case.js
+++ b/test/mjsunit/harmony/unicode-regexp-ignore-case.js
@@ -52,3 +52,7 @@ assertEquals(["\u00e5\u212b\u00c5", "\u00e5"],
              /(.)\1\1/ui.exec("\u00e5\u212b\u00c5"));
 assertEquals(["\u{118aa}\u{118ca}", "\u{118aa}"],
              /(.)\1/ui.exec("\u{118aa}\u{118ca}"));
+
+// Misc.
+assertTrue(/\u00e5\u00e5\u00e5/ui.test("\u212b\u00e5\u00c5"));
+assertTrue(/AB\u{10400}/ui.test("ab\u{10428}"));