Log Message:
Update dbus to 1.10.4:

D-Bus 1.10.4 (2015-11-17)
==

The “Frostburn Canyon” release.

Enhancements:

• GetConnectionCredentials, GetConnectionUnixUser and
  GetConnectionUnixProcessID with argument "org.freedesktop.DBus"
  will now return details of the dbus-daemon itself. This is required
  to be able to call SetEnvironment on systemd.
  (fd.o #92857, Jan Alexander Steffens)

Fixes:

• Make UpdateActivationEnvironment always fail with AccessDenied on the
  system bus. Previously, it was possible to configure it so root could
  call it, but the environment variables were not actually used,
  because the launch helper would discard them.
  (fd.o #92857, Jan Alexander Steffens)

• On Unix with --systemd-activation on a user bus, make
  UpdateActivationEnvironment pass on its arguments to systemd's
  SetEnvironment method, solving inconsistency between the environments
  used for traditional activation and systemd user-service activation.
  (fd.o #92857, Jan Alexander Steffens)

• On Windows, don't crash if <syslog/> or --syslog is used
  (fd.o #92538, Ralf Habacker)

• On Windows, fix a memory leak when setting a DBusError from a Windows
  error (fd.o #92721, Ralf Habacker)

• On Windows, don't go into infinite recursion if we abort the process
  with backtraces enabled (fd.o #92721, Ralf Habacker)

• Fix various failing tests, variously on Windows and cross-platform:
  · don't test system.conf features (users, groups) that only make sense
    on the system bus, which is not supported on Windows
  · don't call _dbus_warn() when we skip a test, since it is fatal
  · fix computation of expected <standard_session_servicedirs/>
  · when running TAP tests, translate newlines to Unix format, fixing
    cross-compiled tests under Wine on Linux
  · don't stress-test refcounting under Wine, where it's really slow
  · stop assuming that a message looped-back to the test will be received
    immediately
  · skip some system bus tests on Windows since they make no sense there
  (fd.o #92538, fd.o #92721; Ralf Habacker, Simon McVittie)