Export of internal Abseil changes

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51e9291d9bc385082b4061fe760b236ba59c79c3 by Abseil Team <absl-team@google.com>:

Cast to uint64_t using braces instead of parentheses.

PiperOrigin-RevId: 372475909

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939fc409855da2639dcaf2d1d4971ca0e0568d03 by Martijn Vels <mvels@google.com>:

Expand # flat nodes into size detailed counters.

PiperOrigin-RevId: 372474608

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54b158c99b32f8a14821ce74fed0f9f836525ce7 by Martijn Vels <mvels@google.com>:

Make copies of sampled cords sampled as well

This applies to the following methods:
- Cord(const Cord&)
- operator=(const Cord&)
- Subcord(...)

PiperOrigin-RevId: 372468160

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876c2581ce008871464e8b471efbb967d150f83b by Andy Getzendanner <durandal@google.com>:

Document the type of an ABSL_FLAGS.OnUpdate() callback.

PiperOrigin-RevId: 372406390
GitOrigin-RevId: 51e9291d9bc385082b4061fe760b236ba59c79c3
Change-Id: Ifb75122cae56b66c28128aee90a63bbb28d93817

1 files changed, 2 insertions, 1 deletions

diff --git a/absl/flags/flag.h b/absl/flags/flag.h
index f09580b0..14209e7b 100644
--- a/absl/flags/flag.h
+++ b/absl/flags/flag.h
@@ -265,6 +265,8 @@ ABSL_NAMESPACE_END
 //
 //   ABSL_FLAG(T, name, default_value, help).OnUpdate(callback);
 //
+// `callback` should be convertible to `void (*)()`.
+//
 // After any setting of the flag value, the callback will be called at least
 // once. A rapid sequence of changes may be merged together into the same
 // callback. No concurrent calls to the callback will be made for the same
@@ -279,7 +281,6 @@ ABSL_NAMESPACE_END
 // Note: ABSL_FLAG.OnUpdate() does not have a public definition. Hence, this
 // comment serves as its API documentation.
 
-
 // -----------------------------------------------------------------------------
 // Implementation details below this section
 // -----------------------------------------------------------------------------