The test setup was as follows:
- Preparse function test() { ... }, get scope allocation data.
- Apply the scope allocation data to (function test() { ... })();
- Compare against normal scope allocation for (function test() { ... })();

But the IIFE is unnecessary - we already disable lazy parsing.

Cleaning this up is needed because in the next CL, I want to fix the Scopes
produced by PreParser in this case:

let f = function g() {
  // Here we should declare g!
}

And that fix will make the variables in
function test() {
  // Here we don't declare test
}
and
(function test() {
  // Here we do declare test
})();
not match any more, so it doesn't make sense to compare them against each other.

BUG=v8:5516

Change-Id: I93d154c6977bb3cbe405b6ca193cf6283df297bc
Reviewed-on: https://chromium-review.googlesource.com/543341Reviewed-by: Daniel Vogelheim <vogelheim@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#46128}