Add default code reviewers into OWNERS

Bug: 33166666
Test: gerrit uploader
Change-Id: Ia7520087449c0b584a49eda77d99df47a3ad904d
diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..d65f614
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1,5 @@
+# Default code reviewers picked from top 3 or more developers.
+# Please update this list if you find better candidates.
+hunga@google.com
+krocard@google.com
+elaurent@google.com