also patch cxx crate from https://github.com/brave/brave-core/commit/… (

#27185)

also patch cxx crate from a22fc31
Change presubmit patch empty line to error to allow upstream patches that do not comply with Brave patching standards

patches/PRESUBMIT.py

@@ -42,7 +42,7 @@ def CheckPatchFile(input_api, output_api):
         return []
 
     return [
-        output_api.PresubmitError(
+        output_api.PresubmitPromptWarning(
             'Patch should not add or remove empty lines at hunk boundaries',
             items)
     ]

patches/third_party-rust-chromium_crates_io-vendor-cxx-1.0.129-include-cxx.h.patch

@@ -0,0 +1,25 @@
+diff --git a/third_party/rust/chromium_crates_io/vendor/cxx-1.0.129/include/cxx.h b/third_party/rust/chromium_crates_io/vendor/cxx-1.0.129/include/cxx.h
+index 3414e4c8a5434f6d43b8bf7a76e634ac0c7d06a5..03fa9bf730156c0926aef35bcf3fc0a98c98a0db 100644
+--- a/third_party/rust/chromium_crates_io/vendor/cxx-1.0.129/include/cxx.h
++++ b/third_party/rust/chromium_crates_io/vendor/cxx-1.0.129/include/cxx.h
+@@ -2,6 +2,7 @@
+ #include <algorithm>
+ #include <array>
+ #include <cassert>
++#include <concepts>
+ #include <cstddef>
+ #include <cstdint>
+ #include <exception>
+@@ -244,6 +245,12 @@ public:
+   bool operator>(const iterator &) const noexcept;
+   bool operator>=(const iterator &) const noexcept;
+
++  using iterator_concept = std::contiguous_iterator_tag;
++  template <std::integral N>
++  friend iterator operator+(N n, const iterator &it) noexcept {
++    return it + n;
++  }
++
+ private:
+   friend class Slice;
+   void *pos;