Coverity 77287: Uninitialized scalar variable.
Coverity 77287: Uninitialized scalar variable.

Coverity complains that ibounds may be used in the "if (transition)"
section without being initialized. We know that it will have been
initialized earlier, in the "if (drawpage)" section, because transition
is never set without drawpage being set.

Update the if to make this clear to coverity.

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