[libc++] Replace `#include ""` with `<>` in libcxx/src/. NFCI.
Our best guess is that the two syntaxes should have exactly equivalent
effects, so, let's be consistent with what we do in libcxx/include/.
I've left `#include "include/x.h"` and `#include "../y.h"` alone
because I'm less sure that they're interchangeable, and they aren't
inconsistent with libcxx/include/ because libcxx/include/ never
does that kind of thing.
Also, use the `_LIBCPP_PUSH_MACROS/POP_MACROS` dance for `<__undef_macros>`,
even though it's technically unnecessary in a standalone .cpp file,
just so we have consistently one way to do it.
Differential Revision: https://reviews.llvm.org/D119561
diff --git a/libcxx/src/stdexcept.cpp b/libcxx/src/stdexcept.cpp
index b9c8970..d08b674 100644
--- a/libcxx/src/stdexcept.cpp
+++ b/libcxx/src/stdexcept.cpp
@@ -6,11 +6,10 @@
//
//===----------------------------------------------------------------------===//
-#include "stdexcept"
-#include "new"
-#include "string"
-#include "system_error"
-
+#include <new>
+#include <stdexcept>
+#include <string>
+#include <system_error>
#ifdef _LIBCPP_ABI_VCRUNTIME
#include "support/runtime/stdexcept_vcruntime.ipp"
