Index: src/wp-admin/includes/class-wp-upgrader.php
===================================================================
--- src/wp-admin/includes/class-wp-upgrader.php	(revision 25615)
+++ src/wp-admin/includes/class-wp-upgrader.php	(working copy)
@@ -1469,7 +1469,7 @@
 			if ( ! file_exists( ABSPATH . '/wp-config.php' ) ) // wp-config.php up one folder in a deployment situation
 				$stop_dirs[] = dirname( ABSPATH );
 			foreach ( array_unique( $stop_dirs ) as $dir ) {
-				if ( file_exists( $dir . '/.svn' ) || file_exists( $dir . '/.git' ) )
+				if ( file_exists( $dir . '/.svn' ) || file_exists( $dir . '/.git' ) || file_exists( $dir . '/.hg' ) || file_exists( $dir . '/.bzr' ) )
 					return false;
 			}
 		}