WordPress at a glance
action is not described

customize_controls_init action-hook . WP 3.4.0

Fires when Customizer controls are initialized, before scripts are enqueued.

Usage

add_action( 'customize_controls_init', 'action_function_name_699' );
function action_function_name_699(){
	// action...
}

Where the hook is called

In file: /wp-admin/customize.php
customize_controls_init
wp-admin/customize.php 112
do_action( 'customize_controls_init' );

Where the hook is used (in WP core)

wp-includes/class-wp-customize-widgets.php 113
add_action( 'customize_controls_init', array( $this, 'customize_controls_init' ) );
wp-includes/class-wp-customize-manager.php 389
add_action( 'customize_controls_init', array( $this, 'prepare_controls' ) );