Revert of Deactivate Parser Bookmarks (patchset #1 id:1 of...

Revert of Deactivate Parser Bookmarks (patchset #1 id:1 of https://codereview.chromium.org/1315173007/ )

Reason for revert:
Tanks performance (Mandreel latency). A simple deactivation will not work.

Original issue's description:
> Deactivate Parser Bookmarks.
>
> Bookmarks may create a race condition which
> results in syntax errors. The more files are parsed
> in parallel the higher the probability that the error
> occurs.
> Unfortunately it is not possible to simply revert the
> CLs related to Bookmarks.
>
> BUG=chromium:527930,chromium:510825
> LOG=Y
>
> Committed: https://crrev.com/129593b40eb69d93ba626601bfda046a95cda0e7
> Cr-Commit-Position: refs/heads/master@{#30594}

TBR=vogelheim@chromium.org,jkummerow@chromium.org,mstarzinger@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=chromium:527930,chromium:510825

Review URL: https://codereview.chromium.org/1304413007

Cr-Commit-Position: refs/heads/master@{#30607}

src/parser.cc

@@ -4184,9 +4184,8 @@ FunctionLiteral* Parser::ParseFunctionLiteral(
     // try to lazy parse in the first place, we'll have to parse eagerly.
     Scanner::BookmarkScope bookmark(scanner());
     if (is_lazily_parsed) {
-      // Deactivate bookmarks for now because they result
-      // race conditions while parsing.
-      Scanner::BookmarkScope* maybe_bookmark = nullptr;
+      Scanner::BookmarkScope* maybe_bookmark =
+          bookmark.Set() ? &bookmark : nullptr;
       SkipLazyFunctionBody(&materialized_literal_count,
                            &expected_property_count, /*CHECK_OK*/ ok,
                            maybe_bookmark);