Revert "[skjson] Unescape strings"

This reverts commit 20fda9ce6a6b8c9913acf65075437c41b6725d4a.

Reason for revert: pesky ASAN

Original change's description:
> [skjson] Unescape strings
> 
> Bug: skia:
> Change-Id: Ie40f498c87cb57ee59c9bea41b1ff3d81a9b5858
> Reviewed-on: https://skia-review.googlesource.com/c/167240
> Reviewed-by: Mike Klein <mtklein@google.com>
> Commit-Queue: Florin Malita <fmalita@chromium.org>

TBR=mtklein@google.com,fmalita@chromium.org

Change-Id: Ic09ee8e4c57d494f68e15c9e5d0c9fd78de8db47
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/c/168263
Reviewed-by: Florin Malita <fmalita@google.com>
Commit-Queue: Florin Malita <fmalita@google.com>
2 files changed