Set error if there is a problem connecting to the DB. Props skeltoac and Potter_System. fixes #5495

git-svn-id: http://svn.automattic.com/wordpress/trunk@6426 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/wp-db.php

@@ -115,6 +115,7 @@ class wpdb {
 <p>We were able to connect to the database server (which means your username and password is okay) but not able to select the <code>$db</code> database.</p>
 <ul>
 <li>Are you sure it exists?</li>
+<li>Does the user <code>".DB_USER."</code> have permission to use the <code>$db</code> database?</li>
 <li>On some systems the name of your database is prefixed with your username, so it would be like username_wordpress. Could that be the problem?</li>
 </ul>
 <p>If you don't know how to setup a database you should <strong>contact your host</strong>. If all else fails you may find help at the <a href='http://wordpress.org/support/'>WordPress Support Forums</a>.</p>");
@@ -462,10 +463,16 @@ class wpdb {
 	 * @param string $message
 	 */
 	function bail($message) { // Just wraps errors in a nice header and footer
-		if ( !$this->show_errors )
+		if ( !$this->show_errors ) {
+			if ( class_exists('WP_Error') )
+				$this->error = new WP_Error('500', $message);
+			else
+				$this->error = $message;
 			return false;
+		}
 		wp_die($message);
 	}
+
 	/**
 	 * Checks wether of not the database version is high enough to support the features WordPress uses
 	 * @global $wp_version