Add tests for `arguments` within function body

...anguage/statements/for-in/var-arguments-fn-strict-init.js

test/language/statements/for-in/var-arguments-fn-strict.js

test/language/statements/variable/arguments-fn-non-strict.js

...tatements/variable/arguments-fn-strict-list-final-init.js

...age/statements/variable/arguments-fn-strict-list-final.js

...tatements/variable/arguments-fn-strict-list-first-init.js

...age/statements/variable/arguments-fn-strict-list-first.js

...atements/variable/arguments-fn-strict-list-middle-init.js

...ge/statements/variable/arguments-fn-strict-list-middle.js

.../statements/variable/arguments-fn-strict-list-repeated.js

...ge/statements/variable/arguments-fn-strict-single-init.js

...anguage/statements/variable/arguments-fn-strict-single.js