No semantics given for empty FunctionBody (section 13) or Program (section 14)

[David-Sarah Hopwood]

In section 13, the FunctionBody production is defined (correctly) as SourceElements_opt, but the semantics is only given for FunctionBody : SourceElements (and refers to the "first" SourceElement within SourceElements, which may not exist).

Similarly for Program : SourceElements_opt in section 14.

Add to the end of section 13, after the paragraph for FunctionBody : SourceElements:

The production FunctionBody : [empty] is evaluated as follows:

1. Return (normal, empty, empty).

Add to section 14, after the paragraph for Program : SourceElements:

The production Program : [empty] is evaluated as follows:

1. Return (normal, empty, empty).

("[empty]" is in small type. Note that using [empty] in a semantics definition as an alternative for Foo_opt is correct; see StringNumericLiteral for a similar example.)