We currently use the outdated contexts list provided by the serializer
to update the receiver (the global proxy) in script contexts. However,
this is not actually necessary, since the global proxy is passed to the
deserializer and replaced as we deserialize.

Originally, the outdated contexts list is to update the global object
field in contexts. This was necessary since at the time the deserializer
creates the native context, the global object has not yet been created.
But the global proxy already exists.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/1488873004

Cr-Commit-Position: refs/heads/master@{#32483}