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, 16 insertions, 0 deletions

diff --git a/absl/container/btree_test.cc b/absl/container/btree_test.cc
index e829e0ba..4d4c64b2 100644
--- a/absl/container/btree_test.cc
+++ b/absl/container/btree_test.cc
@@ -1762,6 +1762,22 @@ TEST(Btree, ValueComp) {
   EXPECT_FALSE(m2.value_comp()(std::make_pair("b", 0), std::make_pair("a", 0)));
 }
 
+// Test that we have the protected members from the std::map::value_compare API.
+// See https://en.cppreference.com/w/cpp/container/map/value_compare.
+TEST(Btree, MapValueCompProtected) {
+  struct key_compare {
+    bool operator()(int l, int r) const { return l < r; }
+    int id;
+  };
+  using value_compare = absl::btree_map<int, int, key_compare>::value_compare;
+  struct value_comp_child : public value_compare {
+    explicit value_comp_child(key_compare kc) : value_compare(kc) {}
+    int GetId() const { return comp.id; }
+  };
+  value_comp_child c(key_compare{10});
+  EXPECT_EQ(c.GetId(), 10);
+}
+
 TEST(Btree, DefaultConstruction) {
   absl::btree_set<int> s;
   absl::btree_map<int, int> m;