Edited Unassigned: array.indexOf(item,start) not supported < IE9 [27973]

v15.1.4 has introduced a problem with array.indexOf with < IE9

Problem was identified in watermark extender but may exist in other places.

Workaround is to use a polyfill along the lines of below:

if (!Array.prototype.indexOf) {
Array.prototype.indexOf = function (elt /*, from*/) {
var len = this.length >>> 0;

var from = Number(arguments[1]) || 0;
from = (from < 0)
? Math.ceil(from)
: Math.floor(from);
if (from < 0)
from += len;

for (; from < len; from++) {
if (from in this &&
this[from] === elt)
return from;
}
return -1;
};
}