This removes the special casing for the lazy compilation stub which used
to have its own code kind, just so that the stack walker would properly
recognize its frame.

Also, by re-using the existing machinery for runtime stubs we no longer
need to copy this stub into the native module and get all the niceties
that come with embedded builtins for free.

Thirdly this will make it easier to start lazy compilation from the
background or to do it on a per-function basis without requiring yet
more special machinery, since {NativeModule::SetLazyBuiltin} no longer
requires access to the Isolate.

Kudos for the inspiration for this cleanup go to Frederik, I merely did
some of the legwork.

R=clemensh@chromium.org
BUG=v8:8834

Change-Id: Iac2b51a2e33fb0e88d25d3632fa18998123ee6c3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1532064Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60365}