[Presentation API] 1-UA presentation support + presenter APIs.

extensions/renderer/resources/media_router_bindings.js

Index: extensions/renderer/resources/media_router_bindings.js
diff --git a/extensions/renderer/resources/media_router_bindings.js b/extensions/renderer/resources/media_router_bindings.js
index 90cf50dacb248c31fc1147100250f3ab23638f35..cb07284b6cc6b2d054eb451cd39f15538ae05bf2 100644
--- a/extensions/renderer/resources/media_router_bindings.js
+++ b/extensions/renderer/resources/media_router_bindings.js
@@ -72,7 +72,8 @@ define('media_router_bindings', [
       'is_local': route.isLocal,
       'custom_controller_path': route.customControllerPath,
       // TODO(imcheng): Remove logic when extension always sets the field.
-      'for_display': route.forDisplay == undefined ? true : route.forDisplay
+      'for_display': route.forDisplay == undefined ? true : route.forDisplay,
+      'is_offscreen_presentation': route.isOffscreenPresentation || false
     });
   }