GitLab

This CL:
* Adds a new chrome page, chrome://device-log for the device log UI
* Eliminates the log from chrome://network, links to device-log

BUG=293739
For browser_resources.grd:
TBR=sky@chromium.org

Review URL: https://codereview.chromium.org/793933003

Cr-Commit-Position: refs/heads/master@{#308422}