Files.app multi-profile: add back migration to old path format.
This CL adds Download folder path migration from /home/chronos/u-hash/Downloads
to /home/chronos/user/Downloads when in the current running environment the
profile path is set as the latter. It can happen when (1) the user enabled and
then disabled the multi-profile flag, or (2) performed restart from about:flags.
In such situations we need back migration not to break configurations.
In addition, inserted path convertion to public functions in open_util so that
paths stored in download history (during flipped path due to about:flags) can
be correctly handled.
BUG=356322,329744
R=hirono@chromium.org
Review URL: https://codereview.chromium.org/
216053002
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@260092 0039d316-1c4b-4281-b951-d872f2087c98