Update VE core submodule to master (5f10e73)

New changes:
a53f101 Update OOjs UI to v0.1.0
1fa518b Update OOjs UI to v0.1.0-pre (15f4156bac)
257af53 Use ContextWidget instead of toolbar inside context menu
5f10e73 Follow-up Ia2076a42: Mark getDescription() as @inheritable for Annotation, Node

Local changes to adjust for the ContextWidget changes.

Change-Id: I47f68f5cf1b9583dab9bd0109fa6504481bdfc67