For each effect the value from the desktop file is added. This will
allow to query all effects which need to be loaded without looking for
the service files.
The functionality is to check whether the effect should be enabled by
default. It's not about whether the effect is enabled by default. This
is also needed as it's currently still taken from the plugin data.
For each effect there is an enum value. The internal mapping of effect to
create, supported and checkDefault is switched to the enum value, though
the methods for the name based variants are still available.
As all effects have always been compiled into the same .so file it's
questionable whether resolving the effects through a library is useful
at all. By linking against the built-in effects we gain the following
advantages:
* don't have to load/unload the KLibrary
* don't have to resolve the create, supported and enabled functions
* no version check required
* no dependency resolving (effects don't use it)
* remove the KWIN_EFFECT macros from the effects
All the effects are now registered in an effects_builtins file which
maps the name to a factory method and supported or enabled by default
methods.
During loading the effects we first check whether there is a built-in
effect by the given name and make a shortcut to create it through that.
If that's not possible the normal plugin loading is used.
Completely unscientific testing [1] showed an improvement of almost 10
msec during loading all the effects I use.
[1] QElapsedTimer around the loading code, start kwin five times, take
average.
REVIEW: 115073
