[PATCH] [libcxx] Fix ctype_byname<wchar_t>::do_is() mask checking.

[Dan Albert]

================
Comment at: src/locale.cpp:1208
@@ +1207,3 @@
+    default:
+        _LIBCPP_ASSERT(false,
+                       "unhandled ctype mask in ctype_byname<wchar_t>::do_is");
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I don't think _LIBCPP_ASSERT() is actually what I want here (since it's usually compiled out). Do we already have something akin to this for _LIBCPP_DEBUG_LEVEL < 1?

http://reviews.llvm.org/D5071