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diff --git a/chromium/components/policy/core/common/cloud/cloud_external_data_store.h b/chromium/components/policy/core/common/cloud/cloud_external_data_store.h
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+++ b/chromium/components/policy/core/common/cloud/cloud_external_data_store.h
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+// Copyright 2013 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 COMPONENTS_POLICY_CORE_COMMON_CLOUD_CLOUD_EXTERNAL_DATA_STORE_H_
+#define COMPONENTS_POLICY_CORE_COMMON_CLOUD_CLOUD_EXTERNAL_DATA_STORE_H_
+
+#include <stddef.h>
+
+#include <string>
+
+#include "base/files/file_path.h"
+#include "base/memory/raw_ptr.h"
+#include "base/memory/ref_counted.h"
+#include "components/policy/core/common/cloud/cloud_external_data_manager.h"
+#include "components/policy/policy_export.h"
+
+namespace base {
+class SequencedTaskRunner;
+}
+
+namespace policy {
+
+class ResourceCache;
+
+// Stores external data referenced by policies. Data is keyed by (key, hash),
+// where |key| is an opaque string that comes from the policy referencing the
+// data, and |hash| is the data's SHA256 hash. Outdated entries are removed by
+// calling Prune() with the list of (key, hash) entries that are to be kept.
+// Instances of this class may be created on any thread and may share the same
+// cache, however:
+// * After creation, the cache and all stores using it must always be accessed
+//   via the same |task_runner| only.
+// * Stores sharing a cache must use different cache_keys to avoid namespace
+//   overlaps.
+// * The cache must outlive all stores using it.
+class POLICY_EXPORT CloudExternalDataStore {
+ public:
+  CloudExternalDataStore(const std::string& cache_key,
+                         scoped_refptr<base::SequencedTaskRunner> task_runner,
+                         ResourceCache* cache);
+  CloudExternalDataStore(const CloudExternalDataStore&) = delete;
+  CloudExternalDataStore& operator=(const CloudExternalDataStore&) = delete;
+  ~CloudExternalDataStore();
+
+  // Removes all entries from the store whose (policy, hash) pair is not found
+  // in |metadata|.
+  using PruningData = std::vector<std::pair<std::string, std::string>>;
+  void Prune(const PruningData& key_hash_pairs_to_keep);
+
+  // Stores |data| under (key, hash). Returns file path if the store
+  // succeeded, and empty FilePath otherwise.
+  base::FilePath Store(const std::string& key,
+                       const std::string& hash,
+                       const std::string& data);
+
+  // Loads the entry at (key, hash) into |data|, verifies that it does not
+  // exceed |max_size| and matches the expected |hash|, then returns true.
+  // Returns empty FilePath if no entry is found at (key, hash), there is a
+  // problem during the load, the entry exceeds |max_size| or does not match
+  // |hash|, and file path otherwise.
+  base::FilePath Load(const std::string& key,
+                      const std::string& hash,
+                      size_t max_size,
+                      std::string* data);
+
+ private:
+  std::string cache_key_;
+
+  // Task runner that |this| runs on.
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
+
+  raw_ptr<ResourceCache> cache_;  // Not owned.
+};
+
+}  // namespace policy
+
+#endif  // COMPONENTS_POLICY_CORE_COMMON_CLOUD_CLOUD_EXTERNAL_DATA_STORE_H_