Add delay to hopper even if it doesn't do anything. Fixes BUKKIT-4061

If a hopper is unable to perform any action during a tick it attempts to do
so every tick from then on. Once it is able to do so it then sets a delay
before attempting to do something again. To avoid excessive CPU usage for
hoppers sitting idle we now apply this delay regardless of the success of
the action.

Remapped by Srg2Source from Bukkit/CraftBukkit@f5388e8f94e2cbab76c2255fd872c289e83100a0