use .IsSet() instead if .Get() != NULL

Change-Id: Ia2b7a719fd398e78cc3b11d4f7b02cb81179f65f
Reviewed-on: https://review.haiku-os.org/c/haiku/+/3488
Reviewed-by: Jérôme Duval <jerome.duval@gmail.com>

app_server memory management: use ObjectDeleter to mark ownership

Make object ownership explicit by use of ObjectDeleter where possible.

Change-Id: I499a00aa3390d1510ae284419e73faffa5166430
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2695
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>
Reviewed-by: Alex von Gluck IV <kallisti5@unixzen.com>

Fixes #7796. The decorator add-on is unloaded when not needed anymore. Avoid assigning offscreen windows a window behaviour (which lives in an add-on). When loading another add-on the offscreen window was still pointing to an invalid window behaviour.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42482 a95241bf-73f2-0310-859d-f6bbb57e9c96

* When allocating a new Window, check the allocation of the DrawingEngine
instance by introducing Window::InitCheck(), use new (nothrow).
* Window is responsible for the DrawingEngine instance, but forgot to delete
it.
* OffscreenWindow is no longer special, every Window owns a DrawingEngine,
no need to delete it anymore, but since it already deletes the HWInterface
instance, it needs to detach the DrawingEngine from it.
* Use new (nothrow) in OffscreenWindow as well.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24308 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Removed severly outdated DebugInfoManager.
* More "layer" cleanup.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24305 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Got rid of the "Layer" part of WindowLayer, ViewLayer, WorkspacesLayer
(now WorkspacesView), OffscreenWindowLayer.
* Renamed ServerScreen.cpp/h to Screen.cpp/h (the class was already called
Screen).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24303 a95241bf-73f2-0310-859d-f6bbb57e9c96

Fixes #7796. The decorator add-on is unloaded when not needed anymore. Avoid assigning offscreen windows a window behaviour (which lives in an add-on). When loading another add-on the offscreen window was still pointing to an invalid window behaviour.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@42482 a95241bf-73f2-0310-859d-f6bbb57e9c96

* When allocating a new Window, check the allocation of the DrawingEngine
instance by introducing Window::InitCheck(), use new (nothrow).
* Window is responsible for the DrawingEngine instance, but forgot to delete
it.
* OffscreenWindow is no longer special, every Window owns a DrawingEngine,
no need to delete it anymore, but since it already deletes the HWInterface
instance, it needs to detach the DrawingEngine from it.
* Use new (nothrow) in OffscreenWindow as well.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24308 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Removed severly outdated DebugInfoManager.
* More "layer" cleanup.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24305 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Got rid of the "Layer" part of WindowLayer, ViewLayer, WorkspacesLayer
(now WorkspacesView), OffscreenWindowLayer.
* Renamed ServerScreen.cpp/h to Screen.cpp/h (the class was already called
Screen).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24303 a95241bf-73f2-0310-859d-f6bbb57e9c96