Patch by Alex Wilson:

* Added archiving/unarchiving support.
* Style cleanup (also some by myself).


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@37540 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/interface/AbstractLayoutItem.h

@@ -13,6 +13,7 @@
 class BAbstractLayoutItem : public BLayoutItem {
 public:
 								BAbstractLayoutItem();
+								BAbstractLayoutItem(BMessage* from);
 	virtual						~BAbstractLayoutItem();
 
 	virtual	BSize				MinSize();
@@ -30,6 +31,8 @@ public:
 	virtual	BSize				BasePreferredSize();
 	virtual	BAlignment			BaseAlignment();
 
+	virtual status_t			Archive(BMessage* into, bool deep = true) const;
+
 private:
 			BSize				fMinSize;
 			BSize				fMaxSize;