Increase coverage for for..of iteration

test/language/statements/for-of/body-dstr-assign-error.js

test/language/statements/for-of/body-dstr-assign.js

test/language/statements/for-of/body-put-error.js

test/language/statements/for-of/generator-close-via-break.js

.../language/statements/for-of/generator-close-via-return.js

test/language/statements/for-of/generator-close-via-throw.js

test/language/statements/for-of/generator-next-error.js

...uage/statements/for-of/iterator-close-get-method-error.js

test/language/statements/for-of/iterator-close-non-object.js

test/language/statements/for-of/iterator-close-via-break.js

test/language/statements/for-of/iterator-close-via-return.js

test/language/statements/for-of/iterator-close-via-throw.js

test/language/statements/for-of/iterator-next-error.js

...tatements/for-of/iterator-next-result-value-attr-error.js