Merge branch 'ls/p4-translation-failure' into maint

Work around "git p4" failing when the P4 depot records the contents
in UTF-16 without UTF-16 BOM.

* ls/p4-translation-failure:
git-p4: handle "Translation of file content failed"
git-p4: add test case for "Translation of file content failed" error

diff --cc git-p4.py
Simple merge