GitLab

Remove ScriptString which is a scoped object keeping a strong handle.
Using wrapper tracing implies that the retaining path for DevTools
shows up properly.

Bug: chromium:810194
Change-Id: Ia5126fdca8d270a9f5700af335735210e4062d61
Reviewed-on: https://chromium-review.googlesource.com/911969
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Cr-Commit-Position: refs/heads/master@{#536993}