Framework: re-added the missing duration property for notices

[klimeryk]

It seems that during the move to global notices, the duration got lost in the process.

/cc @artpi

[artpi]

@klimeryk : I'm not quite sure this prop was there.
Seems like it is only for old notice 'system'
But even when this prop would have been there, the notices wouldnt use it, because I moved the handling of duration to notice component in PR:
#2711

So, by the look of it, it could have been broken for a long time.

If you have reproduction path for the bug it solves, it would be helpful :)

[klimeryk]

I stumbled upon this bug when working on #2262. But you can pick any notices.success in Calypso, add the duration option and test it with and without this patch:

notices.success( 'Doing some testing.', { duration: 5000 } );

Without this patch, the notice is never dismissed. With this patch, it's dismissed after the specified duration.
Looking at the old notices system, the duration option was definitely supported (not sure if it was used anywhere in the actual app though). As I understand it, the old notices system now goes through your global-notices (by listening on its store). And then the render function renders the notices - first the ones from the old system, then from the new one. And in the first part, there's no duration mapping (probably more properties are missing, looking at this list). This PR adds that property - I don't see why it shouldn't work - since the same component is using it few lines below.
I'm sure you know all this, since it's your code :D But I wanted to make sure I understand it correctly too - please correct me if got something wrong.

[gwwar]

🚢