Index: /trunk/src/wp-includes/class-wp-editor.php
===================================================================
--- /trunk/src/wp-includes/class-wp-editor.php	(revision 32165)
+++ /trunk/src/wp-includes/class-wp-editor.php	(revision 32166)
@@ -117,10 +117,4 @@
 			// A cookie (set when a user resizes the editor) overrides the height.
 			$cookie = (int) get_user_setting( 'ed_size' );
-
-			// Upgrade an old TinyMCE cookie if it is still around, and the new one isn't.
-			if ( ! $cookie && isset( $_COOKIE['TinyMCE_content_size'] ) ) {
-				parse_str( $_COOKIE['TinyMCE_content_size'], $cookie );
- 				$cookie = $cookie['ch'];
-			}
 
 			if ( $cookie )