- Enable aggressive lazy inner funcs (make non-declaration funcs lazy, ie let f =
  function() { ... } when --experimental-preparser-scope-analysis is on.
- Turn on variable tracking for lazy top level functions: this makes their inner
  functions skippable.
- Test fix for an testing bug uncovered by this work: when restoring the data
  for the relevant scope, don't assume it's the outermost scope for which we
  have data.
- Fix: if we abort lazy parsing a function, we shouldn't produce any data for
  it.

BUG=v8:5516

Change-Id: I0606fbabb5886dc57dbb53ab5f3fb894ff5d032e
Reviewed-on: https://chromium-review.googlesource.com/518165Reviewed-by: Daniel Vogelheim <vogelheim@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45615}