Whitelist MR extensions for settingsPrivate API.

chrome/common/extensions/api/_permission_features.json

Index: chrome/common/extensions/api/_permission_features.json
diff --git a/chrome/common/extensions/api/_permission_features.json b/chrome/common/extensions/api/_permission_features.json
index 671d5716896496fac5590de40cf709a7e3d7e1b8..02b9261ce3eafbb221a5192e2fd582908381abb4 100644
--- a/chrome/common/extensions/api/_permission_features.json
+++ b/chrome/common/extensions/api/_permission_features.json
@@ -924,11 +924,19 @@
     "channel": "stable",
     "extension_types": ["extension", "legacy_packaged_app"]
   },
-  "settingsPrivate": {
+  "settingsPrivate": [{
     "channel": "trunk",
     "extension_types": ["extension", "platform_app"],
     "location": "component"
   },
+  {
+    "channel": "stable",
+    "extension_types": ["extension"],
+    "whitelist": [
+      "63ED55E43214C211F82122ED56407FF1A807F2A3",  // Media Router Dev
+      "226CF815E39A363090A1E547D53063472B8279FA"   // Media Router Release
+    ]
+  }],
   "signedInDevices": {
     "channel": "dev",
     "extension_types": ["extension", "legacy_packaged_app", "platform_app"]