Segmentation fault in tesseract library used from openalpr

[engycz]

Environment

• Tesseract Version: 4.0.0
• Commit Number: master HEAD
• Platform: Ubuntu 18.04 - Linux ubuntu 4.15.0-23-generic Purely informational, as Zdenko wants to merge parts of this #25-Ubuntu SMP Wed May 23 18:02:16 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux

Current Behavior:

Since the commit ad5ee18 openalpr (https://github.com/openalpr/openalpr) terminates with segfault in in tesseract::LTRResultIterator::WordFontAttributes

Steps to reproduce:

• Install openalpr from repository of your favorite linux distribution
• unpack alpr_segf.tar.gz
• run alpr -c eu --config openalpr.conf segf.jpg

Expected Behavior:

Suggested Fix:

Problem is that when it_->word() is null, it_->row() is also null ad5ee18#diff-643581a59a3a46f463ea80b2c4d99911R172

Before the change the function exited ad5ee18#diff-643581a59a3a46f463ea80b2c4d99911R178