The Scripted and PluginEffectLoader perform locating all effects which
are to be loaded in a thread. When the EffectLoader gets cleared so far
the query did not get canceled. This resulted in effects maybe getting
loaded.
This problems shows on build.kde.org if the test is too fast and tears
down the Effect system while effects are still being queried.
Reviewed-By: David Edmundson
This implementation of the AbstractEffectLoader is able to to load the
scripted KWin Effects. It uses KServiceTypeTrader to find all the
candidates to load.
