Update VE core submodule to master (4366f20)

Use new dm.Surface method for checking undo history state
(hasPastState -> hasBeenModified).

New changes:
38776df [BREAKING CHANGE] Refactor history state methods to better suit uses
3412b41 Localisation updates from https://translatewiki.net.
0c5238c Add system to dm.Surface for staging changes
8f0077c Only hide popups on selection change
4575f82 Fix initial selection when focusing in Firefox
debfd4e Document focus/blur cleanup

Change-Id: Ic66c96a4f64ad82a01a84535ca8cd19332065b37