(bug 48145) Handling "animationstep" event in value variation

This change set ensures that the input extender does not overlap other links
(e.g. the "add qualifier" link when editing a main snak).
Requires change I8d67308208889904ea94a30158c71a705ea18157 in the DataValues
(ValueView) extension.

Change-Id: Id592442afa3d141ad336710cf12d1740418ded75
Merge "(bug 48145) Handling "animationstep" event in value variation"