[libc++][Android] Hide locale Lit features for Bionic

[rprichard]

Summary

Bionic's locale support is simplistic: it only recognizes two locales,
"C" (aka "POSIX") and "C.UTF-8" (aka "en_US.UTF-8"). The locale mode
determines the MB_CUR_MAX, but there is no true locale stuff (e.g.
number formatting). Treat Bionic as if it lacks locales.

libcxx/utils/libcxx/test/dsl.py

def hasAnyLocale(config, locales):
   Different systems may use different names for a locale, so this function checks
   whether any of the passed locale names is supported by setlocale() and returns
   true if one of them works.
 
   This is done by executing a program that tries to set the given locale using
   %{exec} -- this means that the command may be executed on a remote host
   depending on the %{exec} substitution.
   """
+  # Bionic's locale support is simplistic: it only recognizes two locales, "C"
+  # (aka "POSIX") and "C.UTF-8" (aka "en_US.UTF-8"). The locale mode determines
+  # the MB_CUR_MAX, but there is no true locale stuff (e.g. number formatting).
+  # Treat Bionic as if it lacks locales.
   program = """
     #include <stddef.h>
-    #if defined(_LIBCPP_HAS_NO_LOCALIZATION)
+    #include <stdlib.h>
+    #if defined(_LIBCPP_HAS_NO_LOCALIZATION) || defined(__BIONIC__)
       int main(int, char**) { return 1; }
     #else
       #include <locale.h>
       int main(int argc, char** argv) {
         for (int i = 1; i < argc; i++) {
           if (::setlocale(LC_ALL, argv[i]) != NULL) {
             return 0;
           }