Fix where "return/RegEX/" breaks minify

[viable-hartman]

tinymce.min.js contains the following Javascript:

return/^[^:]+:\/\/\/?[^\/]+\//.test(t)

JSShrink does not call the saveRegex method for this Javascript string as it is not a recognized RegEx starting point.

By adding "n" to the strpos test before the saveRegex call, the return/RegEx/ situation is properly handled. In the above case.

When it is not properly handled, the \//.test(t) part of the RegEx is treated as a comment and is improperly truncated for tineymce.min.js.