Fixes gh-1453

related: https://github.com/tc39/Function-prototype-toString-revision/pull/26

This intentionally skips test/built-ins/Function/prototype/toString/*

This reverts commit a01de4a7.

The `length` property should be [[Configurable]]
https://tc39.github.io/ecma262/#sec-function.prototype.bind

Also the test was testing deleting the wrong property.

Fixes #957.

* Add Function.prototype.toString tests for many function forms
* Add non-const computed property name to Function.prototype.toString tests
* Split class method tests into class-expression and class-statement tests
* Add tests for unnamed function expression forms
* Add tests for async (generator) methods in class contexts
* Add test case for Function.prototype.toString on async arrow function

Fix 850

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>

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- No longer valid now that async iteration proposal is at stage 3

This is a continuation of 4a5c52be.

This aligns the tests with this recent change to the F.p.toString proposal:
https://github.com/tc39/Function-prototype-toString-revision/commit/7432ded0e6c465fb53a95fddc7a08608401bd413

Automatic Semicolon Insertion hides an error here by transforming a long
ReturnStatement into a ReturnStatement followed by an ExpressionStatement
that is never reached. The conditions on the second line are thus never
tested.

* Add tests for prototype realm inference

* Add tests for miscellaneous realm concerns

* Add tests for realm of spec-created Errors

In some cases, Error objects produced by the specification are
observable from ECMAScript code. Among these cases, some are further
differentiated in that they occur outside of any built-in function and
may be triggered through syntactic production directly. The current
realm record is commonly interpreted incorrectly under these
circumstances.

Add tests asserting that the expected realm record is used when
constructing such Error objects.

* Add tests for realm use in ArraySpeciesCreate

* Add tests for function realm retrieval

* Add tests for cross-realm behaviors of Symbols

* Add tests for GetValue and PutValue

* Add tests for realm of spec-created Arrays

In some cases, Arrays produced by CreateArrayFromList are observable
from ECMAScript code. Among these cases, two occur outside of any
built-in function and may be triggered through syntactic production
directly. The current realm record is commonly interpreted incorrectly
under these circumstances.

Add tests asserting that the expected realm record is used when
constructing arrays.

* Add test for spec-created object

* fixup! Add tests for realm of spec-created Errors

* fixup! Add tests for realm of spec-created Errors

* fixup! Add tests for prototype realm inference

* fixup! Add tests for miscellaneous realm concerns

* Assert creation of 'arguments' object

Ensure that the 'arguments' object is created in cases where it is not
required by the body but is required by the parameters.

* Add tests for cases that disable "arguments" map

* Add tests for NewTarget override of bound function

* Add test for properties of exotic String objects

Closes #479

According to ES2015, functions created using the FunctionDeclaration
syntax may define "own" properties named "caller" and "arguments" as
long as this is done using the AddRestrictedFunctionProperties abstract
operation.

Remove the assertions that prohibit this extension.

This harness function is not necessary in the majority of cases in which
it is used. Remove its usage to simplify tests and decrease the amount
of domain-specific knowledge necessary to contribute to the test suite.

Persist the harness function itself for use by future tests for ES2015
modules (such a helper is necessary for tests that are interpreted as
module code).

See the proposal at
https://tc39.github.io/Function-prototype-toString-revision/

Note: Already uses the updated DataView function lengths from tc39/ecma262#266 (ES2016 Draft 2015-12-20)

Assert the behavior of the built-in method on the FunctionPrototype and
the usage of the Symbol by the `instanceof` operator.