Bug: vertex_freeze does not return status code as documented

[caroparo]

WebGL_vertex_freeze_RELEASE always returns undefined.

GameMaker-HTML5/scripts/yyBufferVertex.js

Line 353 in c49c594

 function WebGL_vertex_freeze_RELEASE(_buffer) { 

This behavior is different from Windows platform's and what the documentation described.
https://manual-en.yoyogames.com/#t=GameMaker_Language%2FGML_Reference%2FDrawing%2FPrimitives%2Fvertex_freeze.htm

Also: freezing the same vbuffer multiple times seems to cause issues so the vbuff cannot be rendered.