x-doc-messaging.json: MDN says min 6.0 for objects

Update "Cross-document messaging" (window.postMessage) to state that Firefox 6.0 is required for non-strings as data.

https://developer.mozilla.org/en-US/docs/DOM/window.postMessage:

Prior to Gecko 6.0 (Firefox 6.0 / Thunderbird 6.0 / SeaMonkey 2.3), the data parameter must be a string. Starting in Gecko 6.0 (Firefox 6.0 / Thunderbird 6.0 / SeaMonkey 2.3), the data parameter is serialized using the structured clone algorithm.
Adding bit about IE<10 bugs
adding shadow dom
data update
Merge pull request #141 from Hello71/patch-1

x-doc-messaging.json: MDN says min 6.0 for objects
Merge pull request #142 from jakearchibald/patch-1

Adding bit about IE<10 bugs
Merge pull request #143 from kevmoo/master

Canvas: HTML5 Candidate Recommendation
Merge pull request #144 from ebidel/master

Adding Shadow DOM
Referencing script.async = false case
data update
Merge pull request #145 from jakearchibald/patch-2

Referencing script.async = false case
Adding another good resource to CSS3 box sizing.
Added initial WebP support table
All browsers with WebM/VP8 support now have partial webp support
data update
Merge pull request #150 from program247365/master

Add another good resource to the CSS3 Box Sizing links.
Merge pull request #151 from branneman/master

Added WebP support
data update
Update css-gencontent.json

WebKit does support transitions on pseudo-elements.

http://trac.webkit.org/changeset/138632
Added support for intrinsic widths