Removes the range starting at startPageIndex: its pages join the range before.
public bool RemoveRange(int startPageIndex)
The index of the range's first page.
true when a range started there.ISO 32000-2 §12.4.2 and §7.9.7. Removing the range at page index 0 leaves the tree without the entry the clause requires; the labels then read as decimal from 1 up to the first range, with a diagnostic. A mutation.