Add Event interface stub
postMessage with zero or one argument shall throw SyntaxError

per the spec https://html.spec.whatwg.org/multipage/comms.html#dom-window-postmessage
fix structured-cloning with getter properties

Getter property would not be copied during structured-cloning, no Error
is mentioned in the spec (infrastructure.html#structured-clone). The
original case contained 2 independent cases, which can be separated.
Throw TypeError rather than SyntaxError

Thanks for @zcorpan review and comments as:

The algorithms in HTML are layered on top of WebIDL.
The input to the algorithms in HTML are IDL values.

https://html.spec.whatwg.org/multipage/browsers.html#window
 void postMessage(any message, DOMString targetOrigin, optional sequence<Transferable> transfer);

http://heycam.github.io/webidl/#es-operations
 Initialize S to the effective overload set for regular operations (if the operation is a regular operation)
 or for static operations (if the operation is a static operation) with identifier id on interface I and
 with argument count n.
 Let <operation, values> be the result of passing S and arg0..n−1 to the overload resolution algorithm.

http://heycam.github.io/webidl/#dfn-overload-resolution-algorithm
 When n = 0 or 1, step 4 throws TypeError.
Merge pull request #1435 from zqzhang/postMessage-exception

postMessage with zero or one argument shall throw SyntaxError
getter_cloning_should_propagate_exceptions

Agree with the reviewer's comment. Follow the steps defined in 8.2.
3rd param not Transferable should throw TypeError

- with-ports 025, 026 should throw TypeError when the 3rd param isn't
Transferable;
- without-ports 025, dont mean to fix the case. Remove the unused var
obj to avoid confusion in the future.
Remove unnecessary whitespace

Remove unnecessary whitespace
Merge pull request #1438 from siusin/fix-webmessaging-withoutports026-getterclone

fix structured-cloning with getter properties
Fix_coding style

Remove the unnecessary space and replace the tab with spaces
Added test for Element's custom attributes

Based on a discussion in [1], this tests ensures that Element's dataset
properties does not interfere with namespaced attributes with the same
name, but in different namespaces (in the former case, all Element's
dataset properties are stored as attributes with no namespace).

[1] https://critic.hoppipolla.co.uk/showcomment?chain=8907
Merge pull request #1440 from brunoabinader/custom-attrs

Added test for Element's custom attributes; r=Ms2ger
Sort .gitignore
Ignore testharness_runner.html
Merge pull request #1439 from siusin/fix-webmessaging-withport025026-TypeError

WebMessaging__3rd param not Transferable should throw TypeError
Merge pull request #1441 from andreastt/ato/ignore_testharness_runner

Ignore testharness_runner.html
Merge pull request #1414 from inexorabletash/inexorabletash/idb-event-stub

Indexed DB: Add Event interface stub
Add a test for the rendering of option labels.

This commit tests <https://html5.org/r/8868>.
Merge pull request #1443 from Ms2ger/option-label

Add a test for the rendering of option labels.
README: add link to mailing list archive