Native context specialization now lowers monomorphic and
polymorphic accesses to data and constant data properties on
object and/or prototype chain. We don't deal with accessors
yet, and we also completely ignore proxies (which is compatible
with what Crankshaft does).

The code is more or less the straightforward implementation. We
will need to refactor that and extract common patterns once the
remaining bits for full load/store support is in.

CQ_INCLUDE_TRYBOTS=tryserver.v8:v8_linux_nosnap_rel
R=jarin@chromium.org
BUG=v8:4470
LOG=n

Review URL: https://codereview.chromium.org/1396333010

Cr-Commit-Position: refs/heads/master@{#31340}