Imported from GitHub PR #1819

Fix the following error:

absl/random/internal/randen_detect.cc:123:12: error: no member named 'nullopt' in namespace 'std'; did you mean 'absl::nullopt'?
  123 |     return std::nullopt;
      |            ^~~~~~~~~~~~
      |            absl::nullopt
absl/types/optional.h:86:43: note: 'absl::nullopt' declared here
   86 | ABSL_INTERNAL_INLINE_CONSTEXPR(nullopt_t, nullopt,
      |                                           ^
Merge b9a2d39 into 7253ff8

Merging this change closes #1819

COPYBARA_INTEGRATE_REVIEW=#1819 from clementperon:master b9a2d39
PiperOrigin-RevId: 722599523
Change-Id: Ie66cbf9daf3b115668194da8b74acd6a43e12a03

Co-authored-by: Clément Péron <peron.clem@gmail.com>

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Fix buffer overflow the internal demangling function
The overflow can happen during rollback after a parsing
failure, where the null terminator is written without
verifying the buffer bounds.

Credit to www.code-intelligence.com for reporting this issue

PiperOrigin-RevId: 732995553
Change-Id: Ic5075f53e510d270e1784d593defcd53f9121d02

--

Actually use the hint space instruction to strip PAC bits for return
addresses in stack traces as the comment says

https://android.googlesource.com/platform/libcore/+/71f2c75111e87091616f0f3b86bea6c4d345dad1/src/hotspot/os_cpu/linux_aarch64/pauth_linux_aarch64.inline.hpp

PiperOrigin-RevId: 724360415
Change-Id: I691160e43354131a04919765ce283e07c3c933a9