Toolbar: Add a Plugins link to the admin bar menu.

Props colomet, Girishpanchal, afercia, danieltj, rishishah, sabernhardt, joedolson,  huzaifaalmesbah, shailu25, zunaid321, devmuhib, sumitbagthariya16, yuvrajsinh2211, SergeyBiryukov.
Fixes #40683.
Built from https://develop.svn.wordpress.org/trunk@57188


git-svn-id: http://core.svn.wordpress.org/trunk@56699 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/admin-bar.php

@@ -436,6 +436,18 @@ function wp_admin_bar_site_menu( $wp_admin_bar ) {
 
 		// Add the appearance submenu items.
 		wp_admin_bar_appearance_menu( $wp_admin_bar );
+
+		// Add a Plugins link.
+		if ( current_user_can( 'activate_plugins' ) ) {
+			$wp_admin_bar->add_node(
+				array(
+					'parent' => 'site-name',
+					'id'     => 'plugins',
+					'title'  => __( 'Plugins' ),
+					'href'   => admin_url( 'plugins.php' ),
+				)
+			);
+		}
 	}
 }