Make OAuth client id accessible to new ui w/o hardcoding

appengine/swarming/app.yaml

Index: appengine/swarming/app.yaml
diff --git a/appengine/swarming/app.yaml b/appengine/swarming/app.yaml
index 45a658d1df67e1eab0eda75d9a376f32903fa065..1555a4492b90d2136b0d05d3dd06456c01b18b5d 100644
--- a/appengine/swarming/app.yaml
+++ b/appengine/swarming/app.yaml
@@ -70,23 +70,6 @@ handlers:
   secure: always
   login: admin
 
-# TODO(kjlubick): Consider moving elements/ to frontend/ so it is a bit more clear what the folder is about.
-- url: /newui/
-  static_files: elements/index.html
-  upload: elements/index.html
-  secure: always
-  http_headers:
-    Strict-Transport-Security: "max-age=31536000; includeSubDomains; preload"
-    X-Frame-Options: deny
-
-- url: /newui/(.+)
-  static_files: elements/\1-index.html
-  upload: elements/([^/]+)-index.html
-  secure: always
-  http_headers:
-    Strict-Transport-Security: "max-age=31536000; includeSubDomains; preload"
-    X-Frame-Options: deny
-
 - url: /res/(.+)
   static_files: elements/build/\1
   upload: elements/build/(.+)