Grid Lock and Lock-Open Variants

[chances]

Before submitting a new icon request, please confirm the following:

• [x] I have searched all issues to make sure there isn't a request for this icon.
• [x] I have searched the current library to make sure the icon doesn't already exist.
• [x] I understand that brand icons are no longer being added and I can use SimpleIcons for my brand icon needs.
• [x] I only intend to request a single icon (or a few near-identical ones) in this issue.

What would you use this icon for?

When sketching lines on a grid, I'd like a toggle icon that would constrain line segments to the drawing's grid.

Give us an example of what this icon might look like.

e.g. grid-large with an opened lock overlaid:

---

See also #7004.

[boehan]

Like this?

grid-large-lock.zip