Update amp_register_polyfills to register Polyfills only on older W…

…P versions

includes/admin/class-amp-template-customizer.php

@@ -330,8 +330,12 @@ public function add_customizer_scripts() {
 		$dependencies = $asset['dependencies'];
 		$version      = $asset['version'];
 
-		/** This action is documented in includes/class-amp-theme-support.php */
-		do_action( 'amp_register_polyfills' );
+		if ( ! Services::get( 'dependency_support' )->has_support() ) {
+			/**
+			 * Fires when AMP Polyfills should be registered.
+			 */
+			do_action( 'amp_register_polyfills' );
+		}
 
 		wp_enqueue_script(
 			$handle,
@@ -585,8 +589,12 @@ public function add_legacy_customizer_scripts() {
 		$dependencies = $asset['dependencies'];
 		$version      = $asset['version'];
 
-		/** This action is documented in includes/class-amp-theme-support.php */
-		do_action( 'amp_register_polyfills' );
+		if ( ! Services::get( 'dependency_support' )->has_support() ) {
+			/**
+			 * Fires when AMP Polyfills should be registered.
+			 */
+			do_action( 'amp_register_polyfills' );
+		}
 
 		wp_enqueue_script(
 			'amp-customize-controls', // Note: This is not 'amp-customize-controls-legacy' to not break existing scripts that have this dependency.
@@ -645,8 +653,12 @@ public function enqueue_legacy_preview_scripts() {
 			return;
 		}
 
-		/** This action is documented in includes/class-amp-theme-support.php */
-		do_action( 'amp_register_polyfills' );
+		if ( ! Services::get( 'dependency_support' )->has_support() ) {
+			/**
+			 * Fires when AMP Polyfills should be registered.
+			 */
+			do_action( 'amp_register_polyfills' );
+		}
 
 		$asset_file   = AMP__DIR__ . '/assets/js/amp-customize-preview-legacy.asset.php';
 		$asset        = require $asset_file;