dep-resolv: Workaround kf5umbrella errors introduced by v2 change.

So now I remember why kdesrc-build didn't recursively include
dependencies.... we took advantage of the fact that dependencies in
kdesrc-build were just for ordering (not for generating the build list)
by using 'kf5umbrella' as a fake module. This allowed workspace modules
to depend on only kf5umbrella instead of all of the frameworks
individually.

The recent changes to support recursive dependencies broke this, but I
wasn't able to reproduce until I introduce a module-set that actually
ran directly across kf5umbrella as a dependency, which is why I didn't
catch earlier.

This is only a workaround for kf5umbrella in particular, but should tide
things over until I can understand and fix it properly. Apologies for
the inconvenience.

modules/ksb/DependencyResolver.pm

@@ -424,7 +424,8 @@ sub _visitDependencyItemAndDependencies
         debug ("\tdep-resolv: $item:$branch depends on $subItem");
 
         my $subModule = $modulesFromNameRef->{$subItemName};
-        if (!$subModule && !$dependentName) {
+        # TODO: Properly handle 'virtual' dependencies.
+        if (!$subModule && (!$dependentName || $subItemName eq 'kf5umbrella')) {
             whisper (" y[b[*] $dependencyItem depends on $subItem, but no module builds $subItem for this run.");
             _visitDependencyItemAndDependencies($optionsRef, $subItem, $level + 1);
         }