Fixed #2363, Add to Collection.

[vivekbopaliya]

Fixes #2363

Changes:
"Add To Collection" finally working even when viewing another user's sketch list!

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123

[lindapaiste]

Looks good 👍

I did fix this already as part of a larger cleanup in #2353 but that PR is still awaiting approval from @raclim.

This is a bug so we need to fix it ASAP so I'm going to go ahead and merge this so that we can get it fixed in the next release.