Bump abseil-cpp from 20250814.1 to 20260107.0 in /src

[dependabot]

Bumps abseil-cpp from 20250814.1 to 20260107.0.

Release notes

Sourced from abseil-cpp's releases.

Abseil LTS branch, January 2026

Abseil LTS 20260107.0

What's New

• absl::StringResizeAndOverwrite(): A new function in absl/strings/resize_and_overwrite.h that acts as a polyfill for C++23's std::basic_string::resize_and_overwrite. This allows for efficient resizing and in-place initialization of strings, avoiding the overhead of default initialization, which is particularly useful when working with C-style APIs that write directly to a buffer. See abseil/abseil-cpp#1136 for performance notes.
• absl::chunked_queue: A new container in absl/container/chunked_queue.h optimized for use as a FIFO (First-In, First-Out) queue.
• absl::linked_hash_map and absl::linked_hash_set: New hash containers that maintain iteration order matching the insertion order. These are available in absl/container/linked_hash_map.h and absl/container/linked_hash_set.h.
• absl::down_cast: Added to absl/base/casts.h. This function provides a safer way to perform downcasts in a polymorphic type hierarchy. In debug builds (or when hardened asserts are enabled), it uses dynamic_cast to verify the validity of the cast and terminates the program if the cast is invalid. In optimized builds, it uses static_cast for performance.

Breaking Changes

• Mutex Deprecations: Legacy Mutex methods and MutexLock pointer constructors have been marked as deprecated. Users should migrate to the recommended APIs.
• The polyfill type absl::string_view is now an alias for std::string_view in all builds. (abseil/abseil-cpp@9ebd93a)

Baseline: 1e566d994bed60562636342af11b38b8de8d0197 Cherry-pick: d9d76ba372a0a2d553ca40cf75e973d2a696230e Cherry-pick: a3bf78f68584df7ff1304291a64e162266b072ac

Commits

• d407ef1 Cherry-picks for LTS 20260107 (#1990)
• 8d0221c Apply LTS transformations for 20260107 LTS branch (#1989)
• 6d8e1a5 Mark legacy Mutex methods and MutexLock pointer constructors as deprecated
• 685995b cleanup: specify that it's safe to use the class in a signal handler.
• 37147f5 Suppress bugprone-use-after-move in benign cases
• 9391635 StrFormat: format scientific notation without heap allocation
• bbb342c Introduce a legacy copy of GetDebugStackTraceHook API.
• 6bd8e2b Report 1ns instead of 0ns for probe_benchmarks. Some tools incorrectly assume...
• 7599e36 Add absl::chunked_queue
• 60b607b CRC32 version of CombineContiguous for length <= 32.
• Additional commits viewable in compare view

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[jmr]

I'll do this manually and bump the version in CMake and the README at the same time when we start using something from this release (like absl::down_cast).

[dependabot]

OK, I won't notify you again about this release, but will get in touch when a new version is available. If you'd rather skip all updates until the next major or minor version, let me know by commenting @dependabot ignore this major version or @dependabot ignore this minor version. You can also ignore all major, minor, or patch releases for a dependency by adding an ignore condition with the desired update_types to your config file.

If you change your mind, just re-open this PR and I'll resolve any conflicts on it.