Fixed critical bug EXT-4725 (Viewer crashes if try to call from 'Nearby voice' floater)

- reason: LLContextMenu was not not deleted when LLPanelPeopleMenus::ContextMenu was destroyed.
    Associated callbacks were called by Menu Holder for last selected menu_item_call for destroyed LLParticipantList::LLParticipantListMenu
- fix: added destruction of LLContextMenu when LLPanelPeopleMenus::ContextMenu is destructed.

--HG--
branch : product-engine

indra/newview/llpanelpeoplemenus.cpp

@@ -55,6 +55,15 @@ ContextMenu::ContextMenu()
 {
 }
 
+ContextMenu::~ContextMenu()
+{
+	// do not forget delete LLContextMenu* mMenu.
+	// It can have registered Enable callbacks which are called from the LLMenuHolderGL::draw()
+	// via selected item (menu_item_call) by calling LLMenuItemCallGL::buildDrawLabel.
+	// we can have a crash via using callbacks of deleted instance of ContextMenu. EXT-4725
+	if (mMenu) 	mMenu->die();
+}
+
 void ContextMenu::show(LLView* spawning_view, const std::vector<LLUUID>& uuids, S32 x, S32 y)
 {
 	if (mMenu)

indra/newview/llpanelpeoplemenus.h

@@ -45,7 +45,7 @@ class ContextMenu : public LLAvatarListItem::ContextMenu
 {
 public:
 	ContextMenu();
-	virtual ~ContextMenu() {}
+	virtual ~ContextMenu();
 
 	/**
 	 * Show the menu at specified coordinates.