Impacted versions:
Master branch, should by 12.0

Steps to reproduce:
Install a third party addon with localization po file in i18n folder, even loading translation manually, the translation won't work, The console reports error: Translation .... not found in reference pot, skipping.
Reverse the change of  "odoo/tools/translate.py" in this commit, the issue was gone.

Expected behavior:
The po translation works as before.



odoo/tools/translate.py
"""Returns quoted PO term string, with special PO characters escaped"""
    assert r"\n" not in s, "Translation terms may not include escaped newlines ('\\n'), please use only literal newlines! (in '%s')" % s
    return '"%s"' % s.replace('\\','\\\\') \
                     .replace('"','\\"') \
                     .replace('\n', '\\n"\n"')
re_escaped_char = re.compile(r"(\\.)")
re_escaped_replacements = {'n': '\n', 't': '\t',}
def _sub_replacement(match_obj):
    return re_escaped_replacements.get(match_obj.group(1)[1], match_obj.group(1)[1])
def unquote(str):
    """Returns unquoted PO term string, with special PO characters unescaped"""
    return re_escaped_char.sub(_sub_replacement, str[1:-1])
class PoFile(object):