Export of internal Abseil changes

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355b8f7b0070b005d53d94ee4180e95559ba2c88 by Derek Mauro <dmauro@google.com>:

Documentation: don't define absl::Status::ok() in terms of itself

Fixes #1058

PiperOrigin-RevId: 410035651

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31c512c834b3a8979297adc5006c3727a3c6554b by Evan Brown <ezb@google.com>:

Cleanup: move set_params/set_slot_policy into btree_set.h and move map_params into btree_map.h.

Also change some `sizeof(value_type)`s to `sizeof(slot_type)`s and update some comments/variable names referring to values to refer to slots as appropriate in btree.h.

Motivation: preliminary cleanup towards node_btree_*.
PiperOrigin-RevId: 409991342

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3129ca320d61a82f1c9ee8c02a23d25024eea4ab by Abseil Team <absl-team@google.com>:

Use simpler implementation for AddressIsReadable.

In particular, current solution doesn't work on systems configured with large
pid_t space.

PiperOrigin-RevId: 409397716

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f71067f7494b19ce4a2e1df730b934dc931c51b2 by Martijn Vels <mvels@google.com>:

Add Span dependency

PiperOrigin-RevId: 409198889
GitOrigin-RevId: 355b8f7b0070b005d53d94ee4180e95559ba2c88
Change-Id: I7f4df3ec7739fdfde61d8ba983f07a08f6f1c7d7

1 files changed, 74 insertions, 0 deletions

diff --git a/absl/container/btree_set.h b/absl/container/btree_set.h
index f587ca22..8c96e0ed 100644
--- a/absl/container/btree_set.h
+++ b/absl/container/btree_set.h
@@ -55,6 +55,17 @@
 namespace absl {
 ABSL_NAMESPACE_BEGIN
 
+namespace container_internal {
+
+template <typename Key>
+struct set_slot_policy;
+
+template <typename Key, typename Compare, typename Alloc, int TargetNodeSize,
+          bool Multi>
+struct set_params;
+
+}  // namespace container_internal
+
 // absl::btree_set<>
 //
 // An `absl::btree_set<K>` is an ordered associative container of unique key
@@ -724,6 +735,69 @@ void erase_if(btree_multiset<K, C, A> &set, Pred pred) {
   }
 }
 
+namespace container_internal {
+
+// This type implements the necessary functions from the
+// absl::container_internal::slot_type interface for btree_(multi)set.
+template <typename Key>
+struct set_slot_policy {
+  using slot_type = Key;
+  using value_type = Key;
+  using mutable_value_type = Key;
+
+  static value_type &element(slot_type *slot) { return *slot; }
+  static const value_type &element(const slot_type *slot) { return *slot; }
+
+  template <typename Alloc, class... Args>
+  static void construct(Alloc *alloc, slot_type *slot, Args &&...args) {
+    absl::allocator_traits<Alloc>::construct(*alloc, slot,
+                                             std::forward<Args>(args)...);
+  }
+
+  template <typename Alloc>
+  static void construct(Alloc *alloc, slot_type *slot, slot_type *other) {
+    absl::allocator_traits<Alloc>::construct(*alloc, slot, std::move(*other));
+  }
+
+  template <typename Alloc>
+  static void destroy(Alloc *alloc, slot_type *slot) {
+    absl::allocator_traits<Alloc>::destroy(*alloc, slot);
+  }
+
+  template <typename Alloc>
+  static void swap(Alloc * /*alloc*/, slot_type *a, slot_type *b) {
+    using std::swap;
+    swap(*a, *b);
+  }
+
+  template <typename Alloc>
+  static void move(Alloc * /*alloc*/, slot_type *src, slot_type *dest) {
+    *dest = std::move(*src);
+  }
+};
+
+// A parameters structure for holding the type parameters for a btree_set.
+// Compare and Alloc should be nothrow copy-constructible.
+template <typename Key, typename Compare, typename Alloc, int TargetNodeSize,
+          bool Multi>
+struct set_params : common_params<Key, Compare, Alloc, TargetNodeSize, Multi,
+                                  set_slot_policy<Key>> {
+  using value_type = Key;
+  using slot_type = typename set_params::common_params::slot_type;
+  using value_compare =
+      typename set_params::common_params::original_key_compare;
+  using is_map_container = std::false_type;
+
+  template <typename V>
+  static const V &key(const V &value) {
+    return value;
+  }
+  static const Key &key(const slot_type *slot) { return *slot; }
+  static const Key &key(slot_type *slot) { return *slot; }
+};
+
+}  // namespace container_internal
+
 ABSL_NAMESPACE_END
 }  // namespace absl