zephyr-chrome: add OWNERS files

Think the following is good?

1. Unrestricted OWNERS on projects/experimental.
2. A welcoming OWNERS file in the base of the repository.


Change-Id: I0926db70ce1f30df1b3416096a775fd7d3492b26
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/zephyr-chrome/+/2239491
Tested-by: Jack Rosenthal <jrosenth@chromium.org>
Reviewed-by: Jett Rink <jettrink@chromium.org>
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..871719f
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1,8 @@
+# The zephyr-chrome project is open to new contributors and leaders in
+# our team, and always appreciates the additional review assistance.
+# Please do not feel any policital burden to add yourself to the
+# OWNERS file; we welcome you and thank you for your contributions. :)
diff --git a/projects/experimental/OWNERS b/projects/experimental/OWNERS
new file mode 100644
index 0000000..5e9d03e
--- /dev/null
+++ b/projects/experimental/OWNERS
@@ -0,0 +1,3 @@
+# This directory is lighter on the code review. Allow anyone to
+# approve.