SL-15077 Mac Crash destroying LLNotificationSet

Not a fix. Mac sometimes crashes when destroying mItems in LLPersistentNotificationChannel
Decided to try cleaning mItems explicitly to see if it will change callstack, it won't fix the crash, but will help figuring out if source of the issue is in mItems or is LLPersistentNotificationChannel itself

indra/llui/llnotificationptr.h

@@ -27,9 +27,8 @@
 
 // Many classes just store a single LLNotificationPtr
 // and llnotifications.h is very large, so define this ligher header.
-#include <boost/shared_ptr.hpp>
 
 class LLNotification;
-typedef boost::shared_ptr<LLNotification> LLNotificationPtr;
+typedef std::shared_ptr<LLNotification> LLNotificationPtr;
 
 #endif

indra/llui/llnotifications.h

@@ -85,7 +85,6 @@
 
 #include <boost/utility.hpp>
 #include <boost/shared_ptr.hpp>
-#include <boost/enable_shared_from_this.hpp>
 #include <boost/type_traits.hpp>
 #include <boost/signals2.hpp>
 #include <boost/range.hpp>
@@ -304,7 +303,7 @@ typedef boost::shared_ptr<LLNotificationVisibilityRule> LLNotificationVisibility
  */
 class LLNotification  : 
 	boost::noncopyable,
-	public boost::enable_shared_from_this<LLNotification>
+	public std::enable_shared_from_this<LLNotification>
 {
 LOG_CLASS(LLNotification);
 friend class LLNotifications;
@@ -743,7 +742,10 @@ class LLNotificationChannelBase :
 	:	mFilter(filter), 
 		mItems() 
 	{}
-	virtual ~LLNotificationChannelBase() {}
+    virtual ~LLNotificationChannelBase()
+    {
+        mItems.clear();
+    }
 	// you can also connect to a Channel, so you can be notified of
 	// changes to this channel
     LLBoundListener connectChanged(const LLEventListener& slot)
@@ -873,6 +875,7 @@ class LLNotifications :
 {
 	LLSINGLETON(LLNotifications);
 	LOG_CLASS(LLNotifications);
+	virtual ~LLNotifications() {}
 
 public:
 
@@ -1070,7 +1073,11 @@ class LLPersistentNotificationChannel : public LLNotificationChannel
 	LLPersistentNotificationChannel() 
 		:	LLNotificationChannel("Persistent", "Visible", &notificationFilter)
 	{}
-	virtual ~LLPersistentNotificationChannel() {}
+
+    virtual ~LLPersistentNotificationChannel()
+    {
+        mHistory.clear();
+    }
 
 	typedef std::vector<LLNotificationPtr> history_list_t;
 	history_list_t::iterator beginHistory() { sortHistory(); return mHistory.begin(); }

indra/newview/llmediactrl.h

@@ -31,6 +31,7 @@
 
 #include "lluictrl.h"
 #include "llframetimer.h"
+#include "llnotificationptr.h"
 
 class LLViewBorder;
 class LLUICtrlFactory;
@@ -145,7 +146,7 @@ class LLMediaCtrl :
 
 		void setTextureSize(S32 width, S32 height);
 
-		void showNotification(boost::shared_ptr<class LLNotification> notify);
+		void showNotification(LLNotificationPtr notify);
 		void hideNotification();
 
 		void setTrustedContent(bool trusted);