bindings: Retires ScriptWrappableBase mostly.

Removes functions which take ScriptWrappableBase as an argument
in DOMDataStore, V8Wrapper, and V8Binding.

ScriptWrappableBase is still used as the internal pointer in a
wrapper, and it's used to support NPObject.

BUG=235436

Review URL: https://codereview.chromium.org/721383003

git-svn-id: svn://svn.chromium.org/blink/trunk@185370 bbb929c8-8fbe-4397-9dbb-9b2b20218538