Replace string by enum in WebParsedFeaturePolicyDeclaration#feature

third_party/WebKit/Source/platform/feature_policy/FeaturePolicy.h

 // Copyright 2016 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 FeaturePolicy_h
 #define FeaturePolicy_h
 
 #include "platform/PlatformExport.h"
 #include "platform/weborigin/SecurityOrigin.h"
 #include "public/platform/WebFeaturePolicy.h"
 #include "wtf/RefPtr.h"
 #include "wtf/Vector.h"
 #include "wtf/text/WTFString.h"
 
 #include <memory>
 
 namespace blink {
 
 // Returns the corresponding WebFeaturePolicyFeature enum given a feature
 // string.
 PLATFORM_EXPORT WebFeaturePolicyFeature
 getWebFeaturePolicyFeature(const String& feature);
 
 // Converts a JSON feature policy string into a vector of whitelists, one for
-// each feature specified. Unrecognized features are parsed and included
-// but will be filtered out when the policy is constructed. If |messages| is
-// not null, then any errors in the input will cause an error message to be
+// each feature specified. Unrecognized features are filtered out. If |messages|
+// is not null, then any errors in the input will cause an error message to be
 // appended to it.
 PLATFORM_EXPORT WebParsedFeaturePolicy
 parseFeaturePolicy(const String& policy,
                    RefPtr<SecurityOrigin>,
                    Vector<String>* messages);
 
 }  // namespace blink
 
 #endif  // FeaturePolicy_h