The innerNode() of an imageMap is an area, and doesn't have a renderer and therefore can't report a position.
Created attachment 97019 [details]
Postin this patch on behalf of Morgan Winer.
Comment on attachment 97019 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=97019&action=review
> + (WebCore::Frame::visiblePositionForPoint): Changin innerNode() to innerNonSharedNode().
On behalf of Morgan Winer:
Committed revision 88718.