Looks like the global variable i was removed, so no need for this line any more.

dpvc · dpvc · commit 24b01d336b27 · 2016-08-31T11:40:59.000-04:00
diff --git a/unpacked/jax/input/AsciiMath/jax.js b/unpacked/jax/input/AsciiMath/jax.js
@@ -180,8 +180,6 @@
   
   var navigator = {appName: "MathJax"};  // hide the true navigator object
   
-  var i; // avoid global variable used in code below
-  
 /******************************************************************
  *
  *   The following section is ASCIIMathML.js Version 2.2

Original file line number	Diff line number	Diff line change
`@@ -180,8 +180,6 @@`
`180`	`180`
`181`	`181`	`var navigator = {appName: "MathJax"}; // hide the true navigator object`
`182`	`182`
`183`		`- var i; // avoid global variable used in code below`
`184`		`-`
`185`	`183`	`/******************************************************************`
`186`	`184`	`*`
`187`	`185`	`* The following section is ASCIIMathML.js Version 2.2`