isNode() is not called in CKEditor

Confirm this to be an issue. Missing e.g. active icon mark for current markup item.

I did not make a call to isNode in partly because CKEditor seems to have moved away from highlighting buttons depending on the selection. Note that their own image button does not highlight when an image is selected, but it does add a context menu item. Another reason was that at the time I could not figure out how to change a button's state. (Later turned out that buttons do not have states, but the commands associated with them do, and that I now know how to change.)

I did not consider this critical at the time because isNode() should do no processing which changes anything on its own, it's invoked as often as on each keystroke to determine button state, but I can see that some plugins may rely on it internally as well.

We already have an issue about making isNode and invoke receive the same parameters here: #613944: data.node object not present in FCKeditor/CKEditor, so I'll mark this a duplicate of that (can't send the same parameters if it's never invoked hehe).

Un-duplicating the issue and instead noting that this issue needs to be kept in sync #613944: data.node object not present in FCKeditor/CKEditor so that this isNode implementation gets the same element which will be present in invokes' data.node.

Wrote this patch a while ago (originally for #613944) but forgot to post it here...

Slightly revamped that code :)

Sorry, converted @TwoD's code wrongly.

Yep, now it works again. =)

Thanks for reporting, reviewing, and testing! Committed to all branches.

A new development snapshot will be available within the next 12 hours. This improvement will be available in the next official release.