Disable extension Panels on Dev and Canary, except for the whitelist

extensions/common/constants.cc

Index: extensions/common/constants.cc
diff --git a/extensions/common/constants.cc b/extensions/common/constants.cc
index 90957c0d688b20ade49c0630843fe2010dc91940..ff10df9a9119c42088b2d884d582f67cf13ca40f 100644
--- a/extensions/common/constants.cc
+++ b/extensions/common/constants.cc
@@ -93,4 +93,15 @@ const char kQuickOfficeExtensionId[] = "gbkeegbaiigmenfmjfclcdgdpimamgkj";
 const char kMimeHandlerPrivateTestExtensionId[] =
     "oickdpebdnfbgkcaoklfcdhjniefkcji";
 
+const char kProdHangoutsExtensionId[] = "nckgahadagoaajjgafhacjanaoiihapd";
+const char* const kHangoutsExtensionIds[6] = {
+    kProdHangoutsExtensionId,
+    "ljclpkphhpbpinifbeabbhlfddcpfdde",  // Debug.
+    "ppleadejekpmccmnpjdimmlfljlkdfej",  // Alpha.
+    "eggnbpckecmjlblplehfpjjdhhidfdoj",  // Beta.
+    "jfjjdfefebklmdbmenmlehlopoocnoeh",  // Packaged App Debug.
+    "knipolnnllmklapflnccelgolnpehhpl"   // Packaged App Prod.
+    // Keep in sync with _api_features.json and _manifest_features.json.
+};
+
 }  // namespace extension_misc