Build: Fix Gutenberg copy script for font library admin page.

The Gutenberg build copy script was missing `constants.php` from its list of
PHP infrastructure files, causing a fatal error on the Font Library admin page.
Additionally, the `--base-url` argument was missing a trailing slash inside the
`includes_url()` call, resulting in malformed asset URLs.

Also renames the `--fast` build flag to `--skip-types` to match the current
Gutenberg build script option.

Props youknowriad, ellatrix, dd32, westonruter, desrosj.
Fixes #64656.


git-svn-id: https://develop.svn.wordpress.org/trunk@61673 602fd350-edb4-49c9-b593-d223f7449a82

Author: youknowriad

tools/gutenberg/build-gutenberg.js

@@ -145,10 +145,10 @@ async function main() {
 		// On Unix, arguments are passed directly without shell parsing
 		const baseUrlArg =
 			process.platform === 'win32'
-				? '--base-url="includes_url( \'build\' )"'
-				: "--base-url=includes_url( 'build' )";
+				? '--base-url="includes_url( \'build/\' )"'
+				: "--base-url=includes_url( 'build/' )";
 
-		await exec( 'npm', [ 'run', 'build', '--', '--fast', baseUrlArg ], {
+		await exec( 'npm', [ 'run', 'build', '--', '--skip-types', baseUrlArg ], {
 			cwd: gutenbergDir,
 		} );
 

tools/gutenberg/copy-gutenberg-build.js

@@ -39,7 +39,7 @@ const COPY_CONFIG = {
 	// PHP infrastructure files (to wp-includes/build/)
 	phpInfrastructure: {
 		destination: 'build',
-		files: [ 'routes.php', 'pages.php' ],
+		files: [ 'routes.php', 'pages.php', 'constants.php' ],
 		directories: [ 'pages', 'routes' ],
 	},