UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3187.0 Safari/537.36

Steps to reproduce the problem:
1. Open Developer Tools for a tab with any web page opened in it
2. Go to Performance tab
3. Enable 6x CPU throttling

What is the expected behavior?
There should be no high CPU usage

What went wrong?
Built-in Task Manager shows that CPU usage for the tab increases to ~90%, and CPU usage for Developer Tools tab is still ~0.1%

System Monitoring app for Mac OS shows ~92% CPU usage for Chromium Helper process

`top` command in console also lists Chromium Helper:
PID    COMMAND      %CPU TIME     #TH   #WQ  #PORT MEM    PURG   CMPRS  PGRP  PPID  STATE    BOOSTS          %CPU_ME %CPU_OTHRS UID       FAULTS
24123  Chromium Hel 91.1 03:11.73 17/1  1    169   92M-   0B     20M    23852 23852 running  *0[2]           0.00000 0.00000    224256028 199002+

Did this work before? N/A 

Chrome version: 62.0.3187.0  Channel: stable
OS Version: OS X 10.12.6
Flash Version: