Two fixes:

* fix that when you have two different konqueror instances running, when you had a list of closed windows (which is "shared"/synced between windows via bus), and then you pressed "Clear closed items list" button in a window of one of the konqueror process, the closed items lists was not cleared/synced in the other konqueror process because we didn't call to removeClosedWindowItem with the propogate=true, so no dbus syncing was being done.

* the real patch for the nasty konqueror-freeze

- The problem was that instead of removing the window with emitNotifyRemove(), we were actually adding a new one with emitNotifyClosedWindowItem().

- Also, the window to remove is not closedWindowItem but "last", which is as its name says, the last closed window that we have just removed in current konqueror process.