RollbackPageObjectEditTransaction method

RollbackPageObjectEditTransaction restores the snapshot captured by BeginPageObjectEditTransaction, discards every journalled edit and closes the transaction

Use it after a failed CommitPageObjectEditTransaction or whenever the caller decides the edit group must not land

• Calling it outside an open transaction does nothing
• After a rollback the document is byte-identical to the state at transaction begin for all journalled operations

if not Pdf1.CommitPageObjectEditTransaction then
  Pdf1.RollbackPageObjectEditTransaction;