Provide a default implementation for quic_containers.h header.

PiperOrigin-RevId: 391593305
diff --git a/common/platform/default/quiche_platform_impl/quiche_containers_impl.h b/common/platform/default/quiche_platform_impl/quiche_containers_impl.h
new file mode 100644
index 0000000..56ce474
--- /dev/null
+++ b/common/platform/default/quiche_platform_impl/quiche_containers_impl.h
@@ -0,0 +1,22 @@
+// Copyright 2021 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef QUICHE_COMMON_PLATFORM_DEFAULT_QUICHE_PLATFORM_IMPL_QUICHE_CONTAINERS_IMPL_H_
+#define QUICHE_COMMON_PLATFORM_DEFAULT_QUICHE_PLATFORM_IMPL_QUICHE_CONTAINERS_IMPL_H_
+
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Weverything"
+
+#include "absl/container/btree_set.h"
+
+#pragma clang diagnostic pop
+
+namespace quiche {
+
+template <typename Key, typename Compare>
+using QuicheSmallOrderedSetImpl = absl::btree_set<Key, Compare>;
+
+}  // namespace quiche
+
+#endif  // QUICHE_COMMON_PLATFORM_DEFAULT_QUICHE_PLATFORM_IMPL_QUICHE_CONTAINERS_IMPL_H_
diff --git a/quic/platform/api/quic_containers.h b/quic/platform/api/quic_containers.h
index eb16bfa..19795e7 100644
--- a/quic/platform/api/quic_containers.h
+++ b/quic/platform/api/quic_containers.h
@@ -5,7 +5,7 @@
 #ifndef QUICHE_QUIC_PLATFORM_API_QUIC_CONTAINERS_H_
 #define QUICHE_QUIC_PLATFORM_API_QUIC_CONTAINERS_H_
 
-#include "net/quic/platform/impl/quic_containers_impl.h"
+#include "quiche_platform_impl/quiche_containers_impl.h"
 
 namespace quic {
 
@@ -15,7 +15,7 @@
 //
 // DOES NOT GUARANTEE POINTER OR ITERATOR STABILITY!
 template <typename Key, typename Compare = std::less<Key>>
-using QuicSmallOrderedSet = QuicSmallOrderedSetImpl<Key, Compare>;
+using QuicSmallOrderedSet = ::quiche::QuicheSmallOrderedSetImpl<Key, Compare>;
 
 }  // namespace quic