Upstream (most of) ios/web/public

ios/web/public/referrer_util.h

Index: ios/web/public/referrer_util.h
diff --git a/ios/web/public/referrer_util.h b/ios/web/public/referrer_util.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 IOS_WEB_PUBLIC_REFERRER_UTIL_H_
+#define IOS_WEB_PUBLIC_REFERRER_UTIL_H_
+
+#include <string>
+
+#include "ios/web/public/referrer.h"
+#include "net/url_request/url_request.h"
+
+class GURL;
+
+namespace web {
+
+// Returns a sanitized version of |referrer| for use in a Referer header.
+GURL ReferrerForHeader(const GURL& referrer);
+
+// Returns the string that should be sent as the Referer header value for
+// navigating to |destination| from the given referrer, taking the referrer
+// policy into account. Returns an empty string if no Referer should be sent.
+std::string ReferrerHeaderValueForNavigation(
+    const GURL& destination,
+    const web::Referrer& referrer);
+
+// Returns the policy that should be used to process subsequent forwards, if
+// any.
+net::URLRequest::ReferrerPolicy PolicyForNavigation(
+    const GURL& destination,
+    const web::Referrer& referrer);
+
+// Returns the WebReferrerPolicy corresponding to the given policy string
+// (e.g., 'always', 'never', 'origin', 'default'). The string is assumed to
+// be lowercase already. Unrecognized values will be treated as Default.
+ReferrerPolicy ReferrerPolicyFromString(const std::string& policy);
+
+}  // namespace web
+
+#endif  // IOS_WEB_PUBLIC_REFERRER_UTIL_H_