Health.js cleanup. Fixes Vulkan complaints
Reviewed by: @elexis Differential Revision: https://code.wildfiregames.com/D1770
(I missed the unneeded parentheses)
The whitespace here was correct (according to the coding conventions I had to commit)
(Perhaps we can eventually figure out some hack some day that allows designating prototype functions as private, or find some way to actually make them private / local.)
One can always use the (imo, bad) _something convention.