libcxxrt defines bad_array_new_length::what() so move that into a conditional compilation block

llvm-svn: 221025
Cr-Mirrored-From: sso://chromium.googlesource.com/_direct/external/github.com/llvm/llvm-project
Cr-Mirrored-Commit: 1d558b84efb91471b9257cb093c7f59a97ddc3d5
diff --git a/src/new.cpp b/src/new.cpp
index 2fb6e7f..2b37601 100644
--- a/src/new.cpp
+++ b/src/new.cpp
@@ -200,6 +200,12 @@
 {
 }
 
+const char*
+bad_array_new_length::what() const _NOEXCEPT
+{
+    return "bad_array_new_length";
+}
+
 #endif //LIBCXXRT
 
 const char*
@@ -216,12 +222,6 @@
 {
 }
 
-const char*
-bad_array_new_length::what() const _NOEXCEPT
-{
-    return "bad_array_new_length";
-}
-
 #endif // _LIBCPPABI_VERSION
 
 #ifndef LIBSTDCXX