This is a reland of d16bce9d

Original change's description:
> [parser] Removed unnecessary copies
> 
> Bug: v8:8015
> Change-Id: I2ee074559484b9865dc1a27e6ea697ca311ee7ee
> Reviewed-on: https://chromium-review.googlesource.com/1185198
> Reviewed-by: Marja Hölttä <marja@chromium.org>
> Commit-Queue: Florian Sattler <sattlerf@google.com>
> Cr-Commit-Position: refs/heads/master@{#55327}

Bug: v8:8015
Change-Id: I63cf34898f4bbdba84f44e3769301d028ea49965
Reviewed-on: https://chromium-review.googlesource.com/1188142Reviewed-by: Marja Hölttä <marja@chromium.org>
Commit-Queue: Florian Sattler <sattlerf@google.com>
Cr-Commit-Position: refs/heads/master@{#55375}