How do I get Filter Chrome's "Accessibility Permission" to Stick on a Lenovo P2 Phone?

 

There is one way to restrict things on Lenovo, and it is pretty difficult to reverse because the suggestions are built into the system. 

1) Download the SPIN browser

2) Under Settings → Apps → Google Play Store → Modify System Settings, toggle it off. Then select "Disable" under the app icon.  Toggle off modify System settings to prevent the Google play store from reinstalling when disabled. Disable the Google Play Store to prevent installations remotely from another device using the Google account associated with the device.

3) Under Settings → Security, make sure "Unknown Sources" is toggled off. This is to prevent installation of apps from other sources, if downloaded on the SPIN browser or added to device storage using other methods. 

4) Make sure you have no more apps to install, because this will basically Lock you out of doing any more app installations.  In the home screen, press and hold the settings app; there should be a feature at the top right that looks like a lock button. Drag the app to the lock icon. Set a Pin or Pattern that you won't remember. Now you can't undo the modifications made above. 

 

The only downside to all this is you can no longer install apps on the Lenovo device. However, there does not seem to be any better way than this, and it doesn't look like it will change any time soon. So, this may be an option worth considering. You can use what I have written (anonymously of course!) to others if they ask a question similar to mine.