opal/opal — pull request #289 by svoboda-jan (2013-06-01 20:17:32+00:00)
Title: Change indexOf call on Array to if statement so we're compatible with IE 8

After testing the new release of Opal (0.3.44) in IE 8, I came across an error of a `indexOf` function call on `Array`, which is not supported in IE 8.

This PR replaces the `indexOf` function call with an if statement, making it compatible with IE 8 and possibly other older JavaScript implementations.