GitLab

The GDB pretty printers for blink has moved. Update the doc accordingly.

Bug: N/A
Change-Id: Ifce05658d6c207d761fb349d5c4ab877f7e09ae9
Reviewed-on: https://chromium-review.googlesource.com/1029650
Commit-Queue: Kenichi Ishibashi <bashi@chromium.org>
Reviewed-by: Kent Tamura <tkent@chromium.org>
Cr-Commit-Position: refs/heads/master@{#553899}