Mixed case in e-mail address for ORGANIZER causes exception in Sabre\VObject\ITip\Broker.php

[johnkwoods]

We're using sabre/dav 3.22 with sabre/vobject 4.1.6, and we are getting an exception in the parseEventInfo() method of Sabre\VObject\ITip\Broker class. The Exception message is:

"Every instance of the event must have the same organizer."

In the iCal event, this is a recurring meeting, and the original ORGANIZER was First.Last@domain.com. The organizer evidently modified 2 instances. One instance has ORGANIZER as First.Last@domain.com, but the other instance has ORGANIZER as first.last@domain.com.

I believe this issue is due to the following test in parseEventInfo():

if($organizer !== $vevent->ORGANIZER->getNormalizedValue()) {

By adding a few diagnostics into this class, this test is comparing "mailto:First.Last@domain.com" to "mailto:first.last@domain.com", and since they don't match, it throws the exception.

I believe this should be a case-insensitive test. My understanding is that e-mail addresses, themselves, are case-insensitive.

[johnkwoods]

Created a pull request for a potential fix:

40287c8