Export of internal Abseil changes

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a3e58c1870a9626039f4d178d2d599319bd9f8a8 by Matt Kulukundis <kfm@google.com>:

Allow MakeCordFromExternal to take a zero arg releaser.

PiperOrigin-RevId: 298650274

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01897c4a9bb99f3dc329a794019498ad345ddebd by Samuel Benzaquen <sbenza@google.com>:

Reduce library bloat for absl::Flag by moving the definition of base virtual functions to a .cc file.
This removes the duplicate symbols in user translation units and  has the side effect of moving the vtable definition too (re key function)

PiperOrigin-RevId: 298617920

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190f0d3782c63aed01046886d7fbc1be5bca2de9 by Derek Mauro <dmauro@google.com>:

Import GitHub #596: Unbreak stacktrace code for UWP apps

PiperOrigin-RevId: 298600834

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cd5cf6f8c87b35b85a9584e94da2a99057345b73 by Gennadiy Rozental <rogeeff@google.com>:

Use union of heap allocated pointer, one word atomic and two word atomic to represent flags value.

Any type T, which is trivially copy-able and with with sizeof(T) <= 8, will be stored in atomic int64_t.
Any type T, which is trivially copy-able and with with 8 < sizeof(T) <= 16, will be stored in atomic AlignedTwoWords.

We also introducing value storage type to distinguish these cases.

PiperOrigin-RevId: 298497200

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f8fe7bd53bfed601f002f521e34ab4bc083fc28b by Matthew Brown <matthewbr@google.com>:

Ensure a deep copy and proper equality on absl::Status::ErasePayload

PiperOrigin-RevId: 298482742

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a5c9ccddf4b04f444e3f7e27dbc14faf1fcb5373 by Gennadiy Rozental <rogeeff@google.com>:

Change ChunkIterator implementation to use fixed capacity collection of CordRep*. We can now assume that depth never exceeds 91. That makes comparison operator exception safe.

I've tested that with this CL we do not observe an overhead of chunk_end. Compiler optimized this iterator completely.

PiperOrigin-RevId: 298458472

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327ea5e8910bc388b03389c730763f9823abfce5 by Abseil Team <absl-team@google.com>:

Minor cleanups in b-tree code:
- Rename some variables: fix issues of different param names between definition/declaration, move away from `x` as a default meaningless variable name.
- Make init_leaf/init_internal be non-static methods (they already take the node as the first parameter).
- In internal_emplace/try_shrink, update root/rightmost the same way as in insert_unique/insert_multi.
- Replace a TODO with a comment.

PiperOrigin-RevId: 298432836

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8020ce9ec8558ee712d9733ae3d660ac1d3ffe1a by Abseil Team <absl-team@google.com>:

Guard against unnecessary copy in case the buffer is empty. This is important in cases were the user is explicitly tuning their chunks to match PiecewiseChunkSize().

PiperOrigin-RevId: 298366044

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89324441d1c0c697c90ba7d8fc63639805fcaa9d by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 298219363
GitOrigin-RevId: a3e58c1870a9626039f4d178d2d599319bd9f8a8
Change-Id: I28dffc684b6fd0292b94807b88ec6664d5d0e183

1 files changed, 2 insertions, 2 deletions

diff --git a/absl/container/btree_map.h b/absl/container/btree_map.h
index d23f4ee5e648..bb450eadde7c 100644
--- a/absl/container/btree_map.h
+++ b/absl/container/btree_map.h
@@ -318,7 +318,7 @@ class btree_map
   //   Extracts the element at the indicated position and returns a node handle
   //   owning that extracted data.
   //
-  // template <typename K> node_type extract(const K& x):
+  // template <typename K> node_type extract(const K& k):
   //
   //   Extracts the element with the key matching the passed key value and
   //   returns a node handle owning that extracted data. If the `btree_map`
@@ -645,7 +645,7 @@ class btree_multimap
   //   Extracts the element at the indicated position and returns a node handle
   //   owning that extracted data.
   //
-  // template <typename K> node_type extract(const K& x):
+  // template <typename K> node_type extract(const K& k):
   //
   //   Extracts the element with the key matching the passed key value and
   //   returns a node handle owning that extracted data. If the `btree_multimap`