Interesting - we dealt with this issue in CloudTabs, a SaaS for BrowserBox remote browser. The way we handle it, is simply to monitor resource usage with a Python script, issue a warning to the user when their tab or all processes are running hot, then when the rules are triggered we just kill the offending processes (that use too much CPU or RAM).

Chrome has the nice property that you can kill a render process for a tab and often it just takes that tab down, leaving everything else running fine. This plus warning provides minimal user impact while ensuring resources for all.

In the past we experimented with cgroups (both versions) and other mechanisms or limiting but found dynamic monitoring to be the most reliable.