Consistent crash on iOS when rearranging tabs in Grid mode

Steps to reproduce the issue:

1. Enable Tab Style: Grid and Tab Grid Align Bottom settings
2. Open 2 tabs
3. Open the tab view and drag one of the tabs and attempt to "push" the other tab out of the frame
4. Once the other tab leaves the list, stop dragging the selected tab and Orion will crash

Expected behavior:
It shouldn't be possible to push tabs out of the frame.

1.3.9 (7)

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