use Serializable<Proxy> instead of Proxy for instanceof and deleteProperty
remove unnecessary closure
Merge pull request #75 from a14n/remove-unnecessary-closure

remove unnecessary closure
Auto-gen scope on callback creation

I missed this case in my earlier create-a-scope-on-demand CL.  Creating a Callback should create a scope if we're not currently in one.

Review URL: https://chromiumcodereview.appspot.com//14192026
Merge pull request #74 from a14n/improve-methods-with-serializable

use Serializable<Proxy> instead of Proxy for instanceof and deleteProperty
Update to v0.0.22