[subresource_filter] Replace KMP by std::search.

components/subresource_filter/core/common/test_ruleset_utils.h

 // Copyright 2017 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_SUBRESOURCE_FILTER_CORE_COMMON_TEST_RULESET_UTILS_H_
 #define COMPONENTS_SUBRESOURCE_FILTER_CORE_COMMON_TEST_RULESET_UTILS_H_
 
 #include <stdint.h>
 #include <string>
 #include <vector>
 
 #include "base/strings/string_piece.h"
 #include "components/subresource_filter/core/common/proto/rules.pb.h"
 
 namespace subresource_filter {
 namespace testing {
 
+// Creates a blacklist URL rule which targets subresources of any type such that
+// the resource URL ends with |suffix|.
 proto::UrlRule CreateSuffixRule(base::StringPiece suffix);
 
+// Same as CreateUrlRule(pattern, proto::URL_PATTERN_TYPE_WILDCARDED), but the
+// rule applies to the specified |activation_types|, and to no element types.
+// Additionally, it is restricted to a set of |domains| (if provided).
 proto::UrlRule CreateWhitelistRuleForDocument(
     base::StringPiece pattern,
     int32_t activation_types = proto::ACTIVATION_TYPE_DOCUMENT,
     std::vector<std::string> domains = std::vector<std::string>());
 
 }  // namespace testing
 }  // namespace subresource_filter
 
 #endif  // COMPONENTS_SUBRESOURCE_FILTER_CORE_COMMON_TEST_RULESET_UTILS_H_