Move Service Worker %2f validation logic from browser into Blink (3)

content/browser/service_worker/service_worker_utils.cc

 // 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.
 
 #include "content/browser/service_worker/service_worker_utils.h"
 
 #include <string>
 
 #include "base/logging.h"
 #include "base/strings/string_util.h"
@@ skipping 76 matching lines @@
   return true;
 }
 
 // static
 bool ServiceWorkerUtils::ContainsDisallowedCharacter(
     const GURL& scope,
     const GURL& script_url,
     std::string* error_message) {
   if (PathContainsDisallowedCharacter(scope) ||
       PathContainsDisallowedCharacter(script_url)) {
-    *error_message = "The provided scope ('";
-    error_message->append(scope.spec());
-    error_message->append("') or scriptURL ('");
-    error_message->append(script_url.spec());
-    error_message->append("') includes a disallowed escape character.");
+    if (error_message) {
+      *error_message = "The provided scope ('";
+      error_message->append(scope.spec());
+      error_message->append("') or scriptURL ('");
+      error_message->append(script_url.spec());
+      error_message->append("') includes a disallowed escape character.");
+    }
     return true;
   }
   return false;
 }
 
 bool LongestScopeMatcher::MatchLongest(const GURL& scope) {
   if (!ServiceWorkerUtils::ScopeMatches(scope, url_))
     return false;
   if (match_.is_empty() || match_.spec().size() < scope.spec().size()) {
     match_ = scope;
     return true;
   }
   return false;
 }
 
 }  // namespace content