Exclude nested submodules properly. This never worked.

scripts/slave/recipe_modules/sync_submodules/resources/deps2submodules.py

Index: scripts/slave/recipe_modules/sync_submodules/resources/deps2submodules.py
diff --git a/scripts/slave/recipe_modules/sync_submodules/resources/deps2submodules.py b/scripts/slave/recipe_modules/sync_submodules/resources/deps2submodules.py
index 7596609ca687bffb82ee3c78743d82aa56d0c70d..23423e252c096f283f4f04274dc6e63f708a1a3b 100644
--- a/scripts/slave/recipe_modules/sync_submodules/resources/deps2submodules.py
+++ b/scripts/slave/recipe_modules/sync_submodules/resources/deps2submodules.py
@@ -36,14 +36,14 @@ def SanitizeDeps(submods, path_prefix):
 
     parts = name.split('/')[:-1]
     while parts:
-      may_conflict = '/'.join(parts)
+      may_conflict = path_prefix + '/'.join(parts)
       if may_conflict in submods:
         logging.warning('Dropping submodule "%s", because it is nested in '
                         'submodule "%s"', name, may_conflict)
         break
       parts.pop()
-
-    ret[name] = value
+    else:
+      ret[name] = value
   return ret