The templates are being used for many tests reusing the same available function forms.
The format they are provided allow us to extend tests with cases for other tests relying
in the same formats.

Ref #822

Take advantage of a recent extension to the test generation tool in
order to limit duplication.

Per https://github.com/tc39/ecma262/pull/781

test/annexB/built-ins/Date/prototype/setYear/time-clip.js
test/built-ins/Date/prototype/setFullYear/new-value-time-clip.js
test/built-ins/Date/prototype/setMonth/new-value-time-clip.js
- Don't try to test time-clip at the end points, because this is near
impossible to get right (needs to consider time zone offset, dst, local
mean time because of Africa/Monrovia, etc.).

test/built-ins/DataView/prototype/setFloat64/detached-buffer-after-toindex-byteoffset.js
test/built-ins/DataView/prototype/setInt16/detached-buffer-after-toindex-byteoffset.js
- Wasn't update to expect RangeError

test/built-ins/Function/internals/Construct/derived-this-uninitialized-realm.js
- Change ClassDeclaration -> ClassExpression to get completion value

test/built-ins/Function/prototype/toString/AsyncFunction.js
- Add missing \n in expected string
- Also fixed in gh-847

test/built-ins/global/global-object.js
- Add 'var' to make test pass in strict-mode

test/language/block-scope/syntax/redeclaration-in-block/attempt-to-redeclare-function-declaration-with-function-declaration.js
- This is allowed in sloppy mode when Annex B is implemented

test/language/expressions/async-generators/expression-yield-as-statement.js
- Fix calls to then()

test/language/module-code/namespace/internals/own-property-keys-binding-types.js
test/language/module-code/namespace/internals/own-property-keys-sort.js
- Tests weren't updated after removal of @@iterator from module
namespace objects

test/language/module-code/namespace/internals/set-prototype-of-null.js
- Fix syntax error

test/language/statements/async-function/early-errors-no-async-generator.js
- No longer valid now that async iteration proposal is at stage 3

The sameValue assertion should be that the [[Prototype]] is
equal to the class's prototype, not the constructor.