This roll includes:
- https://crrev.com/549003 - DevTools: make pptr tests pass with DCHECKs.
The patch fixes a browser crash that happens during browser close.
As a result, cookies were not saved properly (and thus the flaky test we
had).
Fixes#1537.
This patch introduces a new `pipe` option to the launcher to connect over a pipe.
In certain environments, exposing web socket for remote debugging is a security risk.
Pipe connection eliminates this risk.
