DeclarativeEnvironment NewDeclarativeEnvironment(E:LexicalEnvironment|Null)
Create a new Lexical Environment Record that contains a Declarative Environment Record with no bindings and set E as the outer Lexical Environment.
function NewDeclarativeEnvironment(E){
var env = new LexicalEnvironment;
var envRec = new DeclarativeEnvironment;
env.EnvironmentRecord = envRec;
env.outerLexicalEnvironment = E; // parent
return env;
}