Fix Brightcove detection when another Flash object is on the page

The regex used non-greedy match, but alas it failed on input like this:

    <object class="...> ... class="BrightcoveExperience"

It captured two objects and the intervening HTML.  This commit fixes this by
not allowing a ">" to appear before BrightcoveExperience.

Video in question: http://www.harpercollinschildrens.com/feature/petethecat/