Fix crash clearing chats list before histories.

Telegram/SourceFiles/dialogs/dialogs_indexed_list.cpp

@@ -205,6 +205,7 @@ void IndexedList::remove(Key key, Row *replacedBy) {
 }
 
 void IndexedList::clear() {
+	_list.clear();
 	_index.clear();
 }
 

Telegram/SourceFiles/dialogs/dialogs_list.h

@@ -23,6 +23,10 @@ public:
 	List &operator=(List &&other) = default;
 	~List() = default;
 
+	void clear() {
+		_rows.clear();
+		_rowByKey.clear();
+	}
 	[[nodiscard]] int size() const {
 		return _rows.size();
 	}

Telegram/SourceFiles/dialogs/dialogs_main_list.cpp

@@ -81,6 +81,7 @@ void MainList::clear() {
 		recomputeFullListSize();
 	});
 	const auto notifier = unreadStateChangeNotifier(true);
+	_pinned.clear();
 	_all.clear();
 	_unreadState = UnreadState();
 	_cloudUnreadState = UnreadState();