Fix VASprintfTest on darwin

The way of injecting an error into the printf call was not working on
darwin - the C library still happily format the character. It only
returns an error after we use a wide character that does not fit into a
single byte, so switch the test to use that.

llvm-svn: 295443
diff --git a/lldb/unittests/Utility/VASprintfTest.cpp b/lldb/unittests/Utility/VASprintfTest.cpp
index 73a43dd..0b440942e 100644
--- a/lldb/unittests/Utility/VASprintfTest.cpp
+++ b/lldb/unittests/Utility/VASprintfTest.cpp
@@ -49,11 +49,11 @@
   setlocale(LC_ALL, ".932");
 
   wchar_t Invalid[2];
-  Invalid[0] = 129;
+  Invalid[0] = 0x100;
   Invalid[1] = 0;
   llvm::SmallString<32> Buffer;
   EXPECT_FALSE(Sprintf(Buffer, "%ls", Invalid));
   EXPECT_EQ("<Encoding error>", Buffer);
 
-  setlocale(LC_CTYPE, Current.c_str());
+  setlocale(LC_ALL, Current.c_str());
 }