Steps to reproduce the problem:
1. Launch Chrome app
2. Browse the Web content, ex. Google search , yahoo , mobile01(https://www.mobile01.com/)

What is the expected behavior?
Lower CPU usage

What went wrong?
High CPU usage caused high power consumption and high temperature on mobile device. 
Chrome seems opened 20 processes, and used CPU up to 4.5 hours(in bugreport1).
Would you help clarify, why Chrome keep busy for so long time? Is it abnormal?

Did this work before? Yes It seems work fine before 2018/6/5.

Chrome version: 67.0.3396.68  Channel: stable
OS Version: Android 8.0
Flash Version: 

High CPU usage log in 2 bugreport

Bugreport 1:
PID   TID USER         PR  NI[%CPU]S VIRT  RES PCY CMD             NAME                       
24848 24848 u0_i158      20   0 93.9 S 1.7G  99M  bg dboxed_process2 com.android.chrome:sandboxed
24848 24877 u0_i158      20   0 92.6 R 1.7G  99M  bg TaskSchedulerSe com.android.chrome:sandboxed
25417 25451 u0_i161      20   0 76.8 R 1.7G 113M  bg TaskSchedulerSe com.android.chrome:sandboxed
31526 31567 u0_i171      20   0 75.6 R 1.7G 104M  bg TaskSchedulerSe com.android.chrome:sandboxed
31526 31526 u0_i171      20   0 75.6 S 1.7G 104M  bg dboxed_process9 com.android.chrome:sandboxed
25417 25417 u0_i161      20   0 75.6 S 1.7G 113M  bg boxed_process10 com.android.chrome:sandboxed

Bugreport 2:
  PID   TID USER         PR  NI[%CPU]S VIRT  RES PCY CMD             NAME                       
28826 28858 u0_i165      20   0  101 R 1.7G 102M  bg TaskSchedulerSe com.android.chrome:sandboxed
28826 28826 u0_i165      20   0  100 S 1.7G 102M  bg dboxed_process8 com.android.chrome:sandboxed
31526 31567 u0_i171      20   0 86.2 R 1.7G 104M  bg TaskSchedulerSe com.android.chrome:sandboxed
31526 31526 u0_i171      20   0 86.2 S 1.7G 104M  bg dboxed_process9 com.android.chrome:sandboxed
25417 25451 u0_i161      20   0 77.5 R 1.7G 112M  bg TaskSchedulerSe com.android.chrome:sandboxed
25417 25417 u0_i161      20   0 76.2 S 1.7G 112M  bg boxed_process10 com.android.chrome:sandboxed