Extract the SafeSearch client to a separate directory

chrome/browser/safe_search_api/safe_search_url_checker.h

+// Copyright 2014 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 CHROME_BROWSER_SAFE_SEARCH_API_SAFE_SEARCH_URL_CHECKER_H_
+#define CHROME_BROWSER_SAFE_SEARCH_API_SAFE_SEARCH_URL_CHECKER_H_
+
+#include <stddef.h>
+
+#include "base/callback_forward.h"
+#include "base/containers/mru_cache.h"
+#include "base/macros.h"
+#include "base/memory/scoped_vector.h"
+#include "base/time/time.h"
+#include "net/url_request/url_fetcher_delegate.h"
+#include "url/gurl.h"
+
+namespace net {
+class URLFetcher;
+class URLRequestContextGetter;
+}
+
+// This class uses the SafeSearch API to check the SafeSearch classification
+// of the content on a given URL and returns the result asynchronously
+// via a callback.
+class SafeSearchURLChecker : net::URLFetcherDelegate {
+ public:
+  enum class Classification { SAFE, UNSAFE };
+
+  // Returns whether |url| should be blocked. Called from CheckURL.
+  using CheckCallback = base::Callback<
+      void(const GURL&, Classification classification, bool /* uncertain */)>;
+
+  explicit SafeSearchURLChecker(net::URLRequestContextGetter* context);
+  SafeSearchURLChecker(net::URLRequestContextGetter* context,
+                       size_t cache_size);
+  ~SafeSearchURLChecker() override;
+
+  // Returns whether |callback| was run synchronously.
+  bool CheckURL(const GURL& url, const CheckCallback& callback);
+
+  void SetCacheTimeoutForTesting(const base::TimeDelta& timeout) {
+    cache_timeout_ = timeout;
+  }
+
+ private:
+  struct Check;
+  struct CheckResult {
+    CheckResult(Classification classification, bool uncertain);
+    Classification classification;
+    bool uncertain;
+    base::TimeTicks timestamp;
+  };
+
+  // net::URLFetcherDelegate implementation.
+  void OnURLFetchComplete(const net::URLFetcher* source) override;
+
+  net::URLRequestContextGetter* context_;
+
+  ScopedVector<Check> checks_in_progress_;
+
+  base::MRUCache<GURL, CheckResult> cache_;
+  base::TimeDelta cache_timeout_;
+
+  DISALLOW_COPY_AND_ASSIGN(SafeSearchURLChecker);
+};
+
+#endif  // CHROME_BROWSER_SAFE_SEARCH_API_SAFE_SEARCH_URL_CHECKER_H_