Each effect is able to declare itself as currently being active,
that is transforming windows or painting or screen or doing anything
during the current rendered frame.
This change eliminates the hottest path inside KWin identified by
callgrind.
REVIEW: 102449
This adds a DBus slot to capture a window and the pixmap handle
is passed back via a DBus signal.
Previous code using a shortcut and saving to filesystem is dropped
completely in favor for ksnapshot.
See http://reviewboard.kde.org/r/4814/
svn path=/trunk/KDE/kdebase/workspace/; revision=1175353
Saves an image of the active window into the home directory when triggered.
It uses an OpenGL FBO and by that can include the alpha channel and the decoration shadows.
svn path=/trunk/KDE/kdebase/workspace/; revision=1157682
