Translation: remove support for CiviCRM pre-4.5 l10n file locations

[mlutfy]

Overview

When we added support for "native gettext" in CiviCRM 4.5, the file structure for the "mo" translation files (in the l10n directory) changed. Since few people used native gettext at the time, and since tooling had to be adjusted, we included a fallback mode so that the older file hierarchy still worked.

8 years later, I think we can assume people have fixed their tooling, and use the expected file hierarchy ;)

Before

Fallback mode for mo files in the old location.

After

Fallback removed.

Comments

I plan on adding an option to load extension mo files from the [civicrm.l10n] directory. It's not directly related, but I saw this old code and wanted to tidy up first.

[civibot]

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