Implement PermissionService::GetNextPermissionChange.

content/browser/permissions/permission_service_impl.h

Index: content/browser/permissions/permission_service_impl.h
diff --git a/content/browser/permissions/permission_service_impl.h b/content/browser/permissions/permission_service_impl.h
index 4982b0a04c10c9087f3ecaa0e09a90465faf1bd4..e3c3fb4f750055b4649d67968ed1a2922a1631a0 100644
--- a/content/browser/permissions/permission_service_impl.h
+++ b/content/browser/permissions/permission_service_impl.h
@@ -61,14 +61,29 @@ class PermissionServiceImpl : public mojo::InterfaceImpl<PermissionService> {
       PermissionName permission,
       const mojo::String& origin,
       const mojo::Callback<void(PermissionStatus)>& callback) override;
+  void GetNextPermissionChange(
+      PermissionName permission,
+      const mojo::String& origin,
+      PermissionStatus last_known_status,
+      const mojo::Callback<void(PermissionStatus)>& callback) override;
 
   // mojo::InterfaceImpl.
   void OnConnectionError() override;
 
-  void OnRequestPermissionResponse(int request_id, PermissionStatus status);
+  void OnRequestPermissionResponse(
+      int request_id,
+      PermissionStatus status);
+
+  PermissionStatus GetPermissionStatusFromName(PermissionName permission,
+                                               const GURL& origin);
+  PermissionStatus GetPermissionStatusFromType(PermissionType type,
+                                               const GURL& origin);
+  void ResetPermissionStatus(PermissionType type, const GURL& origin);
 
-  PermissionStatus GetPermissionStatus(PermissionType type, GURL origin);
-  void ResetPermissionStatus(PermissionType type, GURL origin);
+  void OnPermissionStatusChanged(
+      const mojo::Callback<void(PermissionStatus)>& callback,
+      const int* subscription_id,
+      PermissionStatus status);
 
   RequestsMap pending_requests_;
   // context_ owns |this|.