Add upstream

wp-content/plugins/jetpack/modules/pwa/class.jetpack-pwa-helpers.php

@@ -0,0 +1,62 @@
+<?php
+class Jetpack_PWA_Helpers {
+	public static function get_default_manifest_icon_sizes() {
+		// These icon sizes based on conversation here:
+		// https://github.com/GoogleChrome/lighthouse/issues/291
+		return array(
+			192,
+			512,
+		);
+	}
+
+	public static function site_icon_url( $size = 512 ) {
+		$url = get_site_icon_url( $size );
+
+		// Fall back to built-in WordPress icon
+		if ( ! $url && in_array( $size, self::get_default_manifest_icon_sizes() ) ) {
+			$url = esc_url_raw(
+				plugins_url( "modules/pwa/images/wp-$size.png", JETPACK__PLUGIN_FILE )
+			);
+		}
+
+		return $url;
+	}
+
+	public static function get_theme_color() {
+		$theme_color = false;
+
+		// if we have AMP enabled, use those colors?
+		if ( class_exists( 'AMP_Customizer_Settings' ) ) {
+			/* This filter is documented in wp-content/plugins/amp/includes/class-amp-post-template.php */
+			$amp_settings = apply_filters(
+				'amp_post_template_customizer_settings',
+				AMP_Customizer_Settings::get_settings(),
+				null
+			);
+
+			if ( isset( $amp_settings['header_background_color'] ) ) {
+				$theme_color = $amp_settings['header_background_color'];
+			}
+		}
+
+		if ( ! $theme_color && current_theme_supports( 'custom-background' ) ) {
+			$background_color = get_background_color(); // Returns hex key without hash or empty string
+			if ( $background_color ) {
+				$theme_color = "#$background_color";
+			}
+		}
+
+		if ( ! $theme_color ) {
+			$theme_color = '#fff';
+		}
+
+		/**
+		 * Allows overriding the PWA theme color which is used when loading the app.
+		 *
+		 * @since 5.6.0
+		 *
+		 * @param string $theme_color
+		 */
+		return apply_filters( 'jetpack_pwa_background_color', $theme_color );
+	}
+}