Digest signup height change breaks large design animation

[ethanresnick]

On the large design, if the user is focused in the digest email field (causing the upcoming section to grow taller), the animation that scrolls the #upcoming div off the page isn't notified of the height change. The result is that, as the user scrolls down, the upcoming section never goes off the screen entirely, but the top 100px or so of it stay visible. Also, the logo (which was pushed up by the digest details revealing themselves) remains pushed up, such that it goes off the screen.

[ethanresnick]

I explored some potential fixes for this and, rather than trying to notify the leftSidebar component, the sensible and far easier fix is to have the digestSignup component unfocus itself if the user is still focused on it after a certain scroll point.