Most recently used virtual desktop chain is only used in the context of
TabBox and therefore moved into this namespace. KWin uses one desktop
chain for each activity. This is mapped by having multiple DesktopChains.
In addition there is a DesktopChainManager which contains all those
chains which are identified by a QString.
The manager gets connected to the signals emitted by VirtualDesktopManager
for changes in virtual desktops and to signals related to Activities
emitted by Workspace. This means the manager is rather generic as it does
not depend on any other components.
If the ClientModel does not contain any Clients, which can
happen if there is no desktop window, accessing the data of a
ModelIndex returns an invalid QVariant. Because of that it
needs to be ensured that the QVariant is valid before trying to
cast it to a Client Pointer.
BUG: 304620
FIXED-IN: 4.9.1
REVIEW: 105935
The method was missing a check whether the weak pointers in the
internal list got deleted. This could in very unlikely cases
lead to a crash.
In order to verify that adding the null pointer check fixes the
crash a unit test is added to simulate the situation of a
pointer being deleted. This required to add a mock a few
classes of TabBox. A MockTabBoxHandler and MockTabBoxClient are
added implementing the specific interfaces. The DeclarativeView
is completely mocked to make the linker happy. Including the
actual implementation is not possible as it pulls in half of
KWin core.
BUG: 303840
FIXED-IN: 4.9.0
REVIEW: 105645
