[roll] Roll fuchsia [fdf] Separate out device groups and fix issues

Remove the device.h dependency in DeviceGroup by
wrapping the RefPtr<Device> in a weak_ptr wrapper.
This lets us separate out device group classes into
in its own build source set, which will make it
easier for DFv2 classes to depend on.

Fix various issues with device groups:
- Store a string in the device group map, instead of
  a string_view, to have a clear lifetime
- Use natural types for MatchedCompositeInfo instead
   of wires, since it could  potentially get
   deallocated

Original-Bug: 103208
Tests: No new behavior
Original-Reviewed-on: https://fuchsia-review.googlesource.com/c/fuchsia/+/708802
Original-Revision: e91d7e2350945577a8a3d6e375e8e30adcabfef1
GitOrigin-RevId: 5e80575ae69736f080b636f1ad49aaf9a5ed24dd
Change-Id: Ibe77e38c1336a7db2e72c566c7ebef6d1c833f75
diff --git a/stem b/stem
index 386c61f..b093400 100644
--- a/stem
+++ b/stem
@@ -10,7 +10,7 @@
              githooks="integration/git-hooks"
              remote="https://fuchsia.googlesource.com/fuchsia"
              gerrithost="https://fuchsia-review.googlesource.com"
-             revision="d29c4b5831a2d768c5795caa4b27d01c13eb461a"/>
+             revision="e91d7e2350945577a8a3d6e375e8e30adcabfef1"/>
   </projects>
   <hooks>
     <hook name="install-environment"