Block Editor: Remove experimental Social Links blocks

We decided to mark Social Links block as an experimental feature in Gutenberg. In effect, we are moving all related code from WordPress 5.3 release.

Props youknowriad.

Fixes #48263.



git-svn-id: https://develop.svn.wordpress.org/trunk@46543 602fd350-edb4-49c9-b593-d223f7449a82

tools/webpack/packages.js

@@ -1,6 +1,7 @@
 /**
  * External dependencies
  */
+const { DefinePlugin } = require( 'webpack' );
 const LiveReloadPlugin = require( 'webpack-livereload-plugin' );
 const CopyWebpackPlugin = require( 'copy-webpack-plugin' );
 const postcss = require( 'postcss' );
@@ -103,7 +104,6 @@ module.exports = function( env = { environment: 'production', watch: false, buil
 		'block-library/src/rss/index.php': 'wp-includes/blocks/rss.php',
 		'block-library/src/search/index.php': 'wp-includes/blocks/search.php',
 		'block-library/src/shortcode/index.php': 'wp-includes/blocks/shortcode.php',
-		'block-library/src/social-link/index.php': 'wp-includes/blocks/social-link.php',
 		'block-library/src/tag-cloud/index.php': 'wp-includes/blocks/tag-cloud.php',
 	};
 
@@ -204,6 +204,10 @@ module.exports = function( env = { environment: 'production', watch: false, buil
 			],
 		},
 		plugins: [
+			new DefinePlugin( {
+				// Inject the `GUTENBERG_PHASE` global, used for feature flagging.
+				'process.env.GUTENBERG_PHASE': 1,
+			} ),
 			new LibraryExportDefaultPlugin( [
 				'api-fetch',
 				'deprecated',