Fix which keeps from animating keyboardPanningActionHandler when keyboard is animated from a UINavigationController push

[brynbodayle]

There might be a better way to handle this, but basically if you are pushing a view controller onto a UINavigationController stack and you bring up the keyboard before it is pushed, the keyboard animates horizontally instead of vertically. This will make the resizing of the views in the keyboardPanningActionHandler animated which they really don't need to be.