Pull common methods into shell_utils.sh, which can be included by scripts.

So we can stop copying gettop and others all over the place.

Test: manual
Bug: 260003429
Change-Id: Ic1b5d6bec8726d9253fb33ec588e503d6fc8167a
diff --git a/OWNERS b/OWNERS
index 5c7f5ad..57d8994 100644
--- a/OWNERS
+++ b/OWNERS
@@ -3,6 +3,7 @@
 # Since this file affects all Android developers, lock it down. There is still
 # round the world timzeone coverage.
 per-file envsetup.sh = joeo@google.com, jingwen@google.com, lberki@google.com
+per-file shell_utils.sh = joeo@google.com, jingwen@google.com, lberki@google.com
 
 # Finalization scripts
 per-file finalize* = smoreland@google.com, alexbuy@google.com