Enable networking.onc alias to whitelsted apps on stable

BUG=741974

Change-Id: I45e157a0ef6f060fe458fec1df481237c6a01c1f
Reviewed-on: https://chromium-review.googlesource.com/569443Reviewed-by: Rahul Chaturvedi <rkc@chromium.org>
Commit-Queue: Toni Barzic <tbarzic@chromium.org>
Cr-Commit-Position: refs/heads/master@{#486256}

extensions/common/api/_permission_features.json

@@ -345,7 +345,7 @@
     "platforms": ["chromeos"],
     "session_types": ["kiosk.autolaunched"]
   }, {
-    "channel": "dev",
+    "channel": "stable",
     "extension_types": ["extension", "legacy_packaged_app", "platform_app"],
     "platforms": ["chromeos", "mac", "win", "linux"],
     "whitelist": [