Remove most uses of deprecated Language::truncate()

Remove most uses of deprecated Language::truncate()

The Language::truncate() function was split into
Language::truncateForVisual() (which measures characters) and
Language::truncateForDatabase() (which measures bytes) in 1.31, but
the patch which soft-deprecated Language::truncate() didn't actually
remove all the uses in the codebase.  Replace most of those old uses
now, which should actually improve the situation for
non-latin-alphabet users who were getting unfairly squeezed in a
number of places.

Bug: T197492
Change-Id: I2291c69d9df17c1a9e4ab1b7d4cbc73bc51d3ebb