Many blocks untranslated when loaded in another language

[chrisgarrity]

Expected Behavior

Please describe what should happen
When the editor is loaded with a language other than English, the blocks should be translated.

Actual Behavior

Describe what actually happens
If you have your language set to something other than english about 30% of the blocks still show up in the toolbox in English. When you drag them to the workspace they appear translated.

Steps to Reproduce

Explain what someone needs to do in order to see what's described in Actual behavior above
Set your language to something other than English for loading the editor. I.e. change your language on the website before opening the editor, or load the editor with a locale: https://llk.github.io/scratch-gui/develop/?locale=es

All of the basic blocks should be translated, but many will come up in English. Switch to another language, then back to the original, and the blocks will be translated.

I think this regression may be due to the perf changes. /cc @paulkaplan @picklesrus

[paulkaplan]

Oh no! That definitely looks like a regression. I'll look into this right away.

[thisandagain]

Resolved in #4478