Changeset 40398 for trunk/src/wp-includes/js/tinymce/skins/lightgray/fonts/tinymce.eot

Update TinyMCE to 4.5.6. Has many improvements and bug fixes. Changelog: ​https://github.com/tinymce/tinymce/blob/4.5.x/changelog.txt.

Fixes #40305 for trunk.