The Tatar locale data is taken from the recent CLDR tag (v30.0.2), but all other locales kept in the same version (v27). The language data is inserted in between, so it moves a lot of other locale data, which increases the diff.

Before the commit I verified, that generation without Tatar locale files results in no other changes, than generation timestamp in a comment.

Steps to update the data with Tatar locale support:

1. Find out the used CLRD version. The current version is v27. (grep "Common Locale Data Repository" src/corelib/tools/qlocale_data_p.h)
2. Download the same version at http://cldr.unicode.org/index/downloads (file core.zip)
3. Extract the data to a directory, e.g. ~/cldr-27
4. Generate XML data. Probably it would be more convenient to it in the "qtbase" directory: util/local_database/cldr2qlocalexml.py ~/cldr-27/common/main > locales.xml
5. At the same directory: util/local_database/qlocalexml2cpp.py locales.xml pwd
6. Ensure that there is no changes in code (changes in comments are OK).
7. Choose the needed version for Tatar locale. "trunk" seems to be reasonable version at this moment. http://cldr.unicode.org/index/downloads/
8. Download the locale files from seed/main (currently) or common/main (once the locale will be finished) to the main CLDR directory (~/cldr-27/common/main). E.g.: wget http://www.unicode.org/repos/cldr/trunk/seed/main/{tt,tt_RU}.xml; mv tt*xml ~/cldr-27/common/main;
9. Repeat steps 4 and 5.
10. Check that the changes are applied (git diff shows difference in src/corelib/tools/qlocale_data_p.h)
11. Done. Optionally: make a commit.