webrtc-apm: Add OWNERS file

This CL is populating OWNERS file based on the candidates in the Chrome OS OWNERS status sheet.

BUG=b:132095048
TEST=None

Change-Id: I18d96ee99d5e8366028fd45e910e65f6d58fc17f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/webrtc-apm/+/1682705

OWNERS

diff --git a/OWNERS b/OWNERS
new file mode 100644
index 0000000..6ee5ff6
--- /dev/null
+++ b/OWNERS
@@ -0,0 +1 @@
+hychao@google.com