Use constants instead of magic strings for trigger names.

[nlutsenko]

In all of these occurences - we are using a magic string (stirng literal created in place) instead of a constant - just use the constant, since we have triggers.js imported.
There are actually no more occurences of this, so we might as well continue using constants for these in future at all times.

[drew-gross]

I wish JS had real enums :( I find that in practise, this strings-as-fake-enums technique doesn't really end up solving any problems in javascript.

[nlutsenko]

Would be amazing if JS only had those!
The problem we are trying to solve here is actually consistency - since we are using a type, if it's missing - it will be undefined, which would at least surface things better, also provides a much better ability to search and lexer understanding of our stuff.

[flovilmart]

JS has enums, I believe I saw that in douglas crawford

[drew-gross]

They still aren't real enums. The newest version of TypeScript adds real enums, or at least as real as you get in JS land.

[flovilmart]

Should we Object.freeze the Types?

[drew-gross]

surewhynot

[flovilmart]

I though about refactoring a bit the triggers also as it's all over the place now with the hooks controller...