As a first step towards showing builtin frames in stack traces, we will now
push target and new target unconditionally.

Since the various specializations of BuiltinArguments are made redundant by
this change, we can remove them and all related code.

R=bmeurer@chromium.org
BUG=

Review-Url: https://codereview.chromium.org/2074063002
Cr-Commit-Position: refs/heads/master@{#37061}