Use icu4c to implement <wctype.h>.

Pretty useless, because the POSIX APIs are useless for actually
internationalization, but it lets us put this to bed for good.

Bug: http://b/18492914
Test: bionic tests
Change-Id: I4dd0aff66c44b5547039be3ffea806c865b9014a
diff --git a/tests/Android.bp b/tests/Android.bp
index 3e1e13b..643b295 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -385,6 +385,12 @@
     name: "bionic-unit-tests",
     defaults: ["bionic_unit_tests_defaults", "bionic_tests_defaults"],
     clang: true,
+
+    target: {
+        android: {
+            shared_libs: ["libicuuc"],
+        },
+    },
 }
 
 cc_test {