1. In the address bar at the top, type 'about://flags', then press enter.
2. You will then be taken the the page pictured below
3. Once here, hold 'Ctrl' and tap 'F', which gives you a search box
4. Type 'touch' into the search box and set the 'Enable Touch Events' drop-down to 'Disabled'
6. Relaunch Chrome
7. You will now be able to use the Grid Editor.