Export of internal Abseil changes

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cfd7ee2487ed9b5636d8f83d3850c02e3b4a5cb0 by Jorg Brown <jorg@google.com>:

Add union padding to AsTree, to avoid issues on 32-bit MSVC 2015 compilers

alignas() causes compiler errors as per https://godbolt.org/z/vaTKjn
This change uses explicit padding to achieve what we want: https://godbolt.org/z/Mfjhhj

PiperOrigin-RevId: 353211413

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b1ac7430ffdefe58c01b29e9acd182cda4630e1d by Jorg Brown <jorg@google.com>:

Make the casting functions flat() and ring() be static_cast, rather than reinterpret_cast.

PiperOrigin-RevId: 353149543

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c37a6761c31720317c8b0b7db62b693643a88586 by Abseil Team <absl-team@google.com>:

Integrate CordRepRing logic into cord (but do not enable it)

PiperOrigin-RevId: 353135656

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2007fd3045ed6285106795cf8f2e6d792922f5e8 by Abseil Team <absl-team@google.com>:

Fix a typo in the description of ::equal_range(). The correct return is actually a half-open range [first, last).

PiperOrigin-RevId: 353122213

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6683fa2ba7271dd1f575bd7742d97f47a034c9d2 by Abseil Team <absl-team@google.com>:

Integrate CordRepRing logic into cord (but do not enable it)

PiperOrigin-RevId: 353121763
GitOrigin-RevId: cfd7ee2487ed9b5636d8f83d3850c02e3b4a5cb0
Change-Id: I6635163cd634706f5462c4065aa278e6bf193a72

1 files changed, 3 insertions, 4 deletions

diff --git a/absl/container/btree_map.h b/absl/container/btree_map.h
index abc09b0a..ea49d446 100644
--- a/absl/container/btree_map.h
+++ b/absl/container/btree_map.h
@@ -384,9 +384,8 @@ class btree_map
 
   // btree_map::equal_range()
   //
-  // Returns a closed range [first, last], defined by a `std::pair` of two
-  // iterators, containing all elements with the passed key in the
-  // `btree_map`.
+  // Returns a half-open range [first, last), defined by a `std::pair` of two
+  // iterators, containing all elements with the passed key in the `btree_map`.
   using Base::equal_range;
 
   // btree_map::find()
@@ -709,7 +708,7 @@ class btree_multimap
 
   // btree_multimap::equal_range()
   //
-  // Returns a closed range [first, last], defined by a `std::pair` of two
+  // Returns a half-open range [first, last), defined by a `std::pair` of two
   // iterators, containing all elements with the passed key in the
   // `btree_multimap`.
   using Base::equal_range;