Just for the record, your method is inefficient for a lot of implementations of lists/arrays, where it is often far faster to remove from the end than to remove from the beginning.
roel_v is correct to point out this misunderstanding.
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edit: I really don't understand why the parent comment was downvoted and then deleted.
And you don't know what's going into those tabs. That cliché shouldn't be used to excuse positively brain-dead choices.
I'll bite: in arrays, front deletion (like back deletion) can be done in O(1) time. Keep a pointer to the first element, and just increment it upon front deletion (and free the element if necessary). Obviously, you may want to be smart to avoid memory use getting out of hand.
And you don't know what's going into those tabs.
If the array stores references (pointers), which you'd expect with tabs, that is orthogonal to the discussion. Whatever is going into those tabs, a pointer is a pointer.
Actually that's how they often do array-based queues and deques. To help with memory use they let the tail pointer overflow through the end (so you could have tail at index 2 and head at index 8).
Besides, if you really cared about efficiency, you wouldn't be using growable containers... =)