[gn] port 9ed2056

Author: nico

llvm/utils/gn/secondary/libcxx/include/BUILD.gn

@@ -34,6 +34,7 @@ if (current_toolchain == default_toolchain) {
       "_LIBCPP_HAS_NO_LOCALIZATION=",
       "_LIBCPP_HAS_NO_WIDE_CHARACTERS=",
       "_LIBCPP_HAS_NO_STD_MODULES=",
+      "_LIBCPP_INSTRUMENTED_WITH_ASAN=",
       "_LIBCPP_ABI_DEFINES=",
       "_LIBCPP_HARDENING_MODE_DEFAULT=_LIBCPP_HARDENING_MODE_NONE",
       "_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH=",