cros_choose_profile: add Path support

Tweak the PathPrefixDecorator API enough to pass tests.

BUG=None
TEST=CQ passes

Change-Id: I690507a50bcf105b7efc7c729f28c7330c564722
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/3600074
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Sergey Frolov <sfrolov@google.com>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
diff --git a/scripts/cros_choose_profile.py b/scripts/cros_choose_profile.py
index 25cf70b..8b065fe 100644
--- a/scripts/cros_choose_profile.py
+++ b/scripts/cros_choose_profile.py
@@ -35,7 +35,12 @@
     if not prefix or not result:
       # Nothing to do.
       return result
-    elif not isinstance(result, str):
+
+    # Convert Path objects to str.
+    if isinstance(prefix, os.PathLike):
+      prefix = str(prefix)
+
+    if not isinstance(result, str):
       # Transform each path in the collection.
       new_result = []
       for path in result: