This patch is the rest of the lint cleanup minus the other open issue.

chrome/common/json_value_serializer.h

 // Copyright (c) 2009 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_COMMON_JSON_VALUE_SERIALIZER_H_
 #define CHROME_COMMON_JSON_VALUE_SERIALIZER_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/file_path.h"
 #include "base/values.h"
 
 class JSONStringValueSerializer : public ValueSerializer {
  public:
   // json_string is the string that will be source of the deserialization
   // or the destination of the serialization.  The caller of the constructor
   // retains ownership of the string.
-  JSONStringValueSerializer(std::string* json_string)
+  explicit JSONStringValueSerializer(std::string* json_string)
       : json_string_(json_string),
         initialized_with_const_string_(false),
         pretty_print_(false),
         allow_trailing_comma_(false) {
   }
 
   // This version allows initialization with a const string reference for
   // deserialization only.
-  JSONStringValueSerializer(const std::string& json_string)
+  explicit JSONStringValueSerializer(const std::string& json_string)
       : json_string_(&const_cast<std::string&>(json_string)),
         initialized_with_const_string_(true),
         pretty_print_(false),
         allow_trailing_comma_(false) {
   }
 
   ~JSONStringValueSerializer();
 
   // Attempt to serialize the data structure represented by Value into
   // JSON.  If the return value is true, the result will have been written
@@ skipping 51 matching lines @@
   // returned value.
   Value* Deserialize(std::string* error_message);
 
  private:
   FilePath json_file_path_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(JSONFileValueSerializer);
 };
 
 #endif  // CHROME_COMMON_JSON_VALUE_SERIALIZER_H_