Export of internal Abseil changes

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91d76b3ac9edff91f206d9eee60423c39eeeaf93 by Derek Mauro <dmauro@google.com>:

Internal change

PiperOrigin-RevId: 430442277

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9f8a87bcc5cc5b0fd8b7f0318f37d152fd8bea06 by Evan Brown <ezb@google.com>:

Small refactoring to work towards allowing for node_btree_* containers.

- Change common_params::transfer to rely on slot_policy transfer instead of manually doing construct/destruct. Transfer is not construct/destruct for node containers.
- Move maps' value_compare into btree.h from btree_map.h so it can be reused for node_btree_map.h.
- Also add a test for maps' value_compare protected members.

PiperOrigin-RevId: 430245542

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0126e0b6295342317d9c9f0a66e2d7009b858426 by Martijn Vels <mvels@google.com>:

Add CordRepSubString::Create function with hard checks on IsFlat() | IsExternal()

This hardens internal invariants, IsFlat() || IsExternal() is a cheap, single predicted branch, and removes boilerplate code from cord.cc

PiperOrigin-RevId: 429676041

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ed98a92af49d9e238d9f1d1b69fb4eddcd1ccbc7 by Abseil Team <absl-team@google.com>:

tweaks to status.h documentation to reflect general-purpose communication

PiperOrigin-RevId: 429584104
GitOrigin-RevId: 91d76b3ac9edff91f206d9eee60423c39eeeaf93
Change-Id: I54d6d116a564f86a842b983ca76559bf9b388f72

1 files changed, 12 insertions, 9 deletions

diff --git a/absl/container/btree_set.h b/absl/container/btree_set.h
index 78826830..7b6655ad 100644
--- a/absl/container/btree_set.h
+++ b/absl/container/btree_set.h
@@ -61,7 +61,7 @@ template <typename Key>
 struct set_slot_policy;
 
 template <typename Key, typename Compare, typename Alloc, int TargetNodeSize,
-          bool Multi>
+          bool IsMulti>
 struct set_params;
 
 }  // namespace container_internal
@@ -87,7 +87,7 @@ class btree_set
     : public container_internal::btree_set_container<
           container_internal::btree<container_internal::set_params<
               Key, Compare, Alloc, /*TargetNodeSize=*/256,
-              /*Multi=*/false>>> {
+              /*IsMulti=*/false>>> {
   using Base = typename btree_set::btree_set_container;
 
  public:
@@ -427,7 +427,7 @@ class btree_multiset
     : public container_internal::btree_multiset_container<
           container_internal::btree<container_internal::set_params<
               Key, Compare, Alloc, /*TargetNodeSize=*/256,
-              /*Multi=*/true>>> {
+              /*IsMulti=*/true>>> {
   using Base = typename btree_multiset::btree_multiset_container;
 
  public:
@@ -757,6 +757,12 @@ struct set_slot_policy {
   }
 
   template <typename Alloc>
+  static void transfer(Alloc *alloc, slot_type *new_slot, slot_type *old_slot) {
+    construct(alloc, new_slot, old_slot);
+    destroy(alloc, old_slot);
+  }
+
+  template <typename Alloc>
   static void swap(Alloc * /*alloc*/, slot_type *a, slot_type *b) {
     using std::swap;
     swap(*a, *b);
@@ -771,14 +777,11 @@ struct set_slot_policy {
 // 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>> {
+          bool IsMulti>
+struct set_params : common_params<Key, Compare, Alloc, TargetNodeSize, IsMulti,
+                                  /*IsMap=*/false, 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) {