When calculating layout size of the photo overlay text max width is capped at
how wide UITextView was during editing, with the purpose of preserving wrapping
between editor (UITextView) and overlay (CATextLayer).
Previously though, UITextView was set to auto-shrink its width to content size,
which caused max width to not be not enough after changing the font to a bolder variant.
The fix is to pin UITextView's width to view margins so that all available width
is always used when measuring text overlay height.
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