GstRegistryPool Management of a group of #GstRegistry objects The registry pool manages the available registries and plugins in the system. GstRegistry @Returns: @registry: @priority: @registry: @plugin: @filter: @first: @user_data: @Returns: @filter: @first: @user_data: @Returns: @Returns: @type: @Returns: @name: @Returns: @name: @type: @Returns: @flags: @Returns: