unified-email: sanitize account name

Change-Id: Ie7f130e86c75c2fcba429bd58fd67555dda16d25
JIRA: CYAN-3465
Issue: https://jira.cyanogenmod.org/browse/CYAN-3465
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
Merge branch 'upstream/stable/cm-11.0'