Since the public API for deserialization is now just DeserializeOrCompile,
we can trickle down the wire bytes to the deserialization logic, and
avoid the need for duplicating the wire bytes when serializing.

BUG=chromium:657316

Review-Url: https://chromiumcodereview.appspot.com/2433273002
Cr-Commit-Position: refs/heads/master@{#40516}