Element updates 'jarringly' when returning from the Edit Element view to the Page Editor view

[toolness]

This issue has been migrated from mozilla/webmaker-android#1754.

It was originally written by flukeout on Sun May 10 2015 and had the following description:

Make some changes to a text element then return to the page editor, the old text element treatment is visible at first, then it suddenly takes on the new properties - let's make it have the new properties as soon as you see it.