Normalize "\r" newlines in preSaveTransform

The behavior of the different preprocessors differs when given \r or
\r\n newlines. We already normalize the latter here, so may as well do
the former here too.

Bug: T78488
Change-Id: Id6390f64a73ea01088729f25d79103388c1fe7e8
Merge "Normalize "\r" newlines in preSaveTransform"