Update media-views and wp.Backbone.View for Backbone 1.1.

 * Collection set/add/remove/reset methods now return models, not `this`, so they can no longer be chained.
 * Options passed to Backbone.View's constructor are no longer attached automatically. wp.Backbone.View now does this automatically.

See [27170] for Backbone 1.1 itself.

props gcorne.
fixes #26799.

Built from https://develop.svn.wordpress.org/trunk@27171


git-svn-id: https://core.svn.wordpress.org/trunk@27036 1a063a9b-81f0-0310-95a4-ce76da25c4cd