Tracker: Add a try/catch around ModelMenuItem's creation in AddOneAddOn.

ModelMenuItem can throw exceptions if its Model fails to initialize,
and even though we pass a Model in directly, copying the Model
results in opening the underlying file again, which of course may
fail if something changed since our Model was created.

While at it, remove the return value, since it isn't used anywhere.

Should fix #18905.

src/kits/tracker/ContainerWindow.cpp

@@ -237,7 +237,7 @@ end:
 }
 
 
-static bool
+static void
 AddOneAddOn(const Model* model, const char* name, uint32 shortcut,
 	uint32 modifiers, bool primary, void* context,
 	BContainerWindow* window, BMenu* menu)
@@ -247,8 +247,14 @@ AddOneAddOn(const Model* model, const char* name, uint32 shortcut,
 	BMessage* message = new BMessage(kLoadAddOn);
 	message->AddRef("refs", model->EntryRef());
 
-	ModelMenuItem* item = new ModelMenuItem(model, name, message,
-		(char)shortcut, modifiers);
+	ModelMenuItem* item;
+	try {
+		item = new ModelMenuItem(model, name, message,
+			(char)shortcut, modifiers);
+	} catch (...) {
+		delete message;
+		return;
+	}
 
 	const entry_ref* addOnRef = model->EntryRef();
 	AddOnMenuGenerate(addOnRef, menu, window);
@@ -257,8 +263,6 @@ AddOneAddOn(const Model* model, const char* name, uint32 shortcut,
 		params->primaryList->AddItem(item);
 	else
 		params->secondaryList->AddItem(item);
-
-	return false;
 }
 
 
@@ -2891,7 +2895,7 @@ BContainerWindow::AddTrashContextMenus(BMenu* menu)
 
 
 void
-BContainerWindow::EachAddOn(bool (*eachAddOn)(const Model*, const char*,
+BContainerWindow::EachAddOn(void (*eachAddOn)(const Model*, const char*,
 		uint32 shortcut, uint32 modifiers, bool primary, void* context,
 		BContainerWindow* window, BMenu* menu),
 	void* passThru, BStringList& mimeTypes, BMenu* menu)

src/kits/tracker/ContainerWindow.h

@@ -268,7 +268,7 @@ protected:
 		const char*);
 
 	void LoadAddOn(BMessage*);
-	void EachAddOn(bool (*)(const Model*, const char*, uint32 shortcut,
+	void EachAddOn(void (*)(const Model*, const char*, uint32 shortcut,
 			uint32 modifiers, bool primary, void*, BContainerWindow*, BMenu*),
 		void*, BStringList&, BMenu*);