code: public static String toHeaderElement(String name, String value) {
          return OAuth.percentEncode(name) + "=\"" + OAuth.percentEncode(value) + "\"";
      }
docs: Helper method to concatenate a parameter and its value to a pair that can
  be used in an HTTP header. This method percent encodes both parts before
  joining them.
  
  @param name
  the OAuth parameter name, e.g. oauth_token
  @param value
  the OAuth parameter value, e.g. 'hello oauth'
  @return a name/value pair, e.g. oauth_token="hello%20oauth"