Intl402 ed2

Add tests for String.fromCodePoint

Negative reform

Fix 11.13.1-4-29gs.js incorrect comment explanation (master)

SyntaxError => TypeError for writing to a non-writeable field.

Fixes #372

Add tests for WeakMap

Improve coverage of SetIteratorPrototype

The `negative` frontmatter tag expresses an expectation for the behavior
of the test file as a whole. The `assert.throws` helper function offers
more fine-grained control over expectations because it may be applied to
specific statements and expressions. This makes it preferable in cases
where it may be used (i.e. when the test body does not describe a syntax
error or early error).

Re-implement assertions for errors to use the `assert.throws` helper
function wherever possible.

Move tests for the FunctionPrototype intrinsic

Re-organize class tests

Test262 maintains most tests for the FunctionPrototype intrinsic within
the `test/built-ins/Function/prototype/` directory. Two tests are
defined within the otherwise-empty `test/built-ins/intrinsics/`
directory; relocate them to the canonical directory for consistency and
discoverability.

The `test/language/class/` directory contains a small subset of
Test262's tests for ES2015 classes. The majority of tests for classes
are organized within `test/language/statements/class/`.

- Move the tests that rely on the ClassDeclaration syntactic form from
  `test/language/class/` to `test/language/statements/class/`.
- Move the test that relies on the ClassExpression syntactic form from
  `test/language/class/` to `test/language/expressions/class/`.

Clean-up test comments and remove invalid tests

Add test for built-in accessor properties names

Unicode escape identifiers

Re-organize generator tests

- Re-organize existing tests for identifiers
  Name files according to their content (not their ES5 ID). Move tests
  for IdentifierName and LabelIdentifier to more appropriate directories.
- Simplify and correct tests
  Instead of asserting successful runtime evaluation using `eval`, rely
  on the test runner's ability to detect syntax errors. Update the test
  bodies to test the grammar referenced by their ES5 ID and
  description--the IdentifierStart pattern.
- Use `negative` frontmatter to assert SyntaxErrors
- Remove redundant tests
- Use `assert.equal` helper function
- Add equivalent tests for literal unicode chars
- Add tests for variable-length unicode escape

The `test/language/generators/` directory contained a single file that
concerned generators derived both from syntactic form and from a
built-in function.

Refactor this test into two files and place each in the appropriate
directory.

Intl constructors are no longer able to initialize arbitrary objects as Intl objects. Update tests accordingly.

- 15.10.2.15-3-1 and 15.10.2.15-3-2 are both invalid (U+002F (SOLIDUS) instead of U+005C (REVERSE SOLIDUS) was used to start an escape sequence).
- 15.10.4.1-2 and 15.10.2.2-1 are identical tests, delete the latter.
- Update tests to avoid using runTestCase() function.
- Update multiple test infos to point to correct algorithm step (CharacterRange step 6 instead of step 1).

Fix, update and improve coverage of MapIteratorPrototype

Formalize tests for built-in Promise methods 

Implement `raw` flag

Add tests for Map

Uniformly and exhaustively test the generic aspects of the static- and
instance Promise methods, including:

- function `length` properties
- function `name` properties
- method property descriptors