Patch from GM to make more implicit bools explicit since we can't stop MSVC warning about this in headers and to warn is the MSVC default. No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@192548 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/locale b/include/locale
index 40e33c2..ab7a7d4 100644
--- a/include/locale
+++ b/include/locale
@@ -3331,7 +3331,7 @@
             bool __more_needed = __trailing_sign ||
                                  (__p < 2)       ||
                                  (__p == 2 && __pat.field[3] != static_cast<char>(money_base::none));
-            bool __sb = __flags & ios_base::showbase;
+            bool __sb = (__flags & ios_base::showbase) != 0;
             if (__sb || __more_needed)
             {
                 typename string_type::const_iterator __sym_space_end = __sym.begin();