Remove atomics usage

Author: Avaer Kazmer

src/Graphics.js

@@ -120,7 +120,7 @@ HTMLCanvasElement.prototype.getContext = (oldGetContext => function getContext(t
     const canvas = this;
     const gl = oldGetContext.call(canvas, type, init);
     // gl.version = match[1] === 'webgl2' ? 2 : 1;
-    gl.id = Atomics.add(GlobalContext.xrState.id, 0) + 1;
+    gl.id = ++GlobalContext.xrState.id[0];
     gl._proxyContext = null;
     Object.defineProperty(gl, 'canvas', { // Object.defineProperty to avoid proxying
       get() {

src/WindowVm.js

@@ -232,7 +232,7 @@ const _clean = o => {
   return result;
 };
 const _makeWindow = (options = {}) => {
-  const id = Atomics.add(GlobalContext.xrState.id, 0, 1) + 1;
+  const id = ++GlobalContext.xrState.id[0];
   const window = new WorkerVm({
     initModule: './Window.js',
     args: {