GitLab

When using hosted mode, --custom-devtools-frontend specifies the URL
rather than the path to the debug devtools bundle. This change fixes
the workflow of opening a bundled DevTools instance on a hosted
DevTools instance.

R=dgozman@chromium.org

Change-Id: I6fcc4641c8d1dff324fb9a1096d3b38e10c9344f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1751182Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#686376}