Add GetCollapsible() accessor to BSplitView/Layout.

headers/os/interface/SplitView.h

@@ -42,6 +42,7 @@ public:
 									bool invalidateLayout);
 			void				SetItemWeight(BLayoutItem* item, float weight);
 
+			bool				GetCollapsible(int32 index) const;
 			void				SetCollapsible(bool collapsible);
 			void				SetCollapsible(int32 index, bool collapsible);
 			void				SetCollapsible(int32 first, int32 last,

src/kits/interface/SplitLayout.cpp

@@ -462,6 +462,13 @@ BSplitLayout::SetItemWeight(BLayoutItem* item, float weight)
 }
 
 
+bool
+BSplitLayout::GetCollapsible(int32 index) const
+{
+	return _ItemLayoutInfo(ItemAt(index))->isCollapsible;
+}
+
+
 void
 BSplitLayout::SetCollapsible(bool collapsible)
 {

src/kits/interface/SplitLayout.h

@@ -61,6 +61,7 @@ public:
 									bool invalidateLayout);
 			void				SetItemWeight(BLayoutItem* item, float weight);
 
+			bool				GetCollapsible(int32 index) const;
 			void				SetCollapsible(bool collapsible);
 			void				SetCollapsible(int32 index, bool collapsible);
 			void				SetCollapsible(int32 first, int32 last,

src/kits/interface/SplitView.cpp

@@ -152,6 +152,13 @@ BSplitView::SetItemWeight(BLayoutItem* item, float weight)
 }
 
 
+bool
+BSplitView::GetCollapsible(int32 index) const
+{
+	return fSplitLayout->GetCollapsible(index);
+}
+
+
 void
 BSplitView::SetCollapsible(bool collapsible)
 {