Implement old flexbox for supportedProperty

[cvle]

This PR does the following:

• supportedProperty now accepts an optional options parameter
• Test fixture might include multiple properties for certain props
• implement old flexbox 2009 props for supportedProperty

This PR (and previous PRs) only implements the supportedProperty part and we still need to properly implement the supportedValue counterpart.

44 failing tests left (all IE and Edge related).

[cvle]

I'm still experimenting on how we could support the uc browser...

[cvle]

I think for the UC browser we should utilize browser sniffing and handle it separately as the ability to feature detect is inconsistent. I would keep all UC browser related code separately, so we can delete it once the UC browser becomes 100% feature detectable...

[cvle]

Let's move on for now and deal with UC browser later on..

[kof]

Is UC specific stuff really UC specific or just old spec? So we are not able to feature detect the old spec?

[cvle]

It is really UC specific. So when you feature detect UC you will find support for the new spec and the old spec even though it only supports the old one.

[kof]

It is really UC specific. So when you feature detect UC you will find support for the new spec and the old spec even though it only supports the old one.

In this weird case it seems like we have to do the sniffing.

[kof]

Is there any good simple way to identify UC browser?

[cvle]

Yeah bowser simply does this: /ucbrowser/i.test(ua). Pretty simple.

[kof]

Just wanted to write this.

[kof]

I hope its reliable across all the devices and versions.

[kof]

Btw. what about a more complex feature testing. For e.g. creating an element, positioning it with flex, looking up its calculated position.

[cvle]

You'll slow down all other browsers, just because one browser is behaving weirdly. I don't want to support a misbehaving browser on the cost of others.

[cvle]

And they hopefully fix these issues with the next major release. So this will be a temporary workaround anyway.

[kof]

You'll slow down all other browsers, just because one browser is behaving weirdly. I don't want to support a misbehaving browser on the cost of others.

It depends, could be done once relatively quickly and cached, most probably a matter of < 1ms

[cvle]

Your suggestion would make sense if we need a permanent solution. But once the UC Browser updates its rendering engine we would revert to the solution of this PR as it is faster and more consistent with the rest. I prefer using browser sniffing and just flag the flex props of the new spec as false positives.

[cvle]

I applied changes to the PR

[kof]

merged, looks good!