let coro malloc/free use wrappers

Summary: The coroutine library has non-elidable wrappers for alloc/dealloc. They directly call `operator new` and `operator delete` but, of course, they have conditionals. Switch to the wrappers which handle the conditionals.

Reviewed By: luciang

Differential Revision: D33181403

fbshipit-source-id: ab8d56634569b82680b36d6b72fb9ff7f5c05f19

folly/experimental/coro/detail/Malloc.cpp

@@ -17,14 +17,13 @@
 #include <folly/experimental/coro/detail/Malloc.h>
 
 #include <folly/BenchmarkUtil.h>
-
-#include <new>
+#include <folly/lang/New.h>
 
 extern "C" {
 
 FOLLY_NOINLINE
 void* folly_coro_async_malloc(std::size_t size) {
-  void* p = ::operator new(size);
+  auto p = folly::operator_new(size);
 
   // Add this after the call to prevent the compiler from
   // turning the call to operator new() into a tailcall.
@@ -35,13 +34,7 @@ void* folly_coro_async_malloc(std::size_t size) {
 
 FOLLY_NOINLINE
 void folly_coro_async_free(void* ptr, std::size_t size) {
-#if __cpp_sized_deallocation >= 201309
-  ::operator delete(ptr, size);
-#else
-  // sized delete is not available on iOS before 10.0
-  (void)size;
-  ::operator delete(ptr);
-#endif
+  folly::operator_delete(ptr, size);
 
   // Add this after the call to prevent the compiler from
   // turning the call to operator delete() into a tailcall.