Work around a failure in Windows 10 jump lists.

Work around a failure in Windows 10 jump lists.

We've had several reports that launching saved sessions from the
Windows 10 jump list fails; Changyu Li reports that this is because we
create those IShellLink objects with a command line string starting
with @, and in Windows 10 that causes the SetArguments method to
silently do the wrong thing.

(cherry picked from commit 8bf5c1b31f1a1449d694e3604e293b0831eb2657)