(Only the first 10 of 21 ports in this commit are shown above. )
www/firefox: update to 55.0
This is the last release to support RUST=off. Later versions
remove non-Rust codepaths e.g., via encoding_rs.
Changes: https://www.mozilla.org/firefox/55.0/releasenotes/
PR: 216541219963
Security: 555b244e-6b20-4546-851f-d8eb7d6c1ffa
MFH: 2017Q3