Registers a new user script message handler in script world with name world_name.
Different from webkit.user_content_manager.UserContentManager.registerScriptMessageHandler,
when using this function to register the handler, the connected signal is
script-message-with-reply-received, and a reply provided by the user is expected.
Otherwise, the user will receive a default undefined value.
Registers a new user script message handler in script world with name world_name.
Different from webkit.user_content_manager.UserContentManager.registerScriptMessageHandler, when using this function to register the handler, the connected signal is script-message-with-reply-received, and a reply provided by the user is expected. Otherwise, the user will receive a default undefined value.
If null is passed as the world_name, the default world will be used. See webkit.user_content_manager.UserContentManager.registerScriptMessageHandler for full description.
Registering a script message handler will fail if the requested name has been already registered before.
The registered handler can be unregistered by using webkit.user_content_manager.UserContentManager.unregisterScriptMessageHandler.