Move loaded history pointer to message view

When it was in the history manager, it wouldn't get unloaded when the room was unloaded.

Hopefully fixes #136

ui/message-view.go

@@ -51,6 +51,7 @@ type MessageView struct {
 
 	// Used for locking
 	loadingMessages int32
+	historyLoadPtr  uint64
 
 	_widestSender     uint32
 	_prevWidestSender uint32
@@ -109,6 +110,7 @@ func (view *MessageView) Unload() {
 	view.ScrollOffset = 0
 	view._widestSender = 5
 	view.prevMsgCount = -1
+	view.historyLoadPtr = 0
 	view.messagesLock.Unlock()
 	view.msgBufferLock.Unlock()
 	view.messageIDLock.Unlock()

ui/view-main.go

@@ -461,13 +461,15 @@ func (view *MainView) LoadHistory(roomID id.RoomID) {
 	// Update the "Loading more messages..." text
 	view.parent.Render()
 
-	history, err := view.matrix.GetHistory(roomView.Room, 50)
+	history, newLoadPtr, err := view.matrix.GetHistory(roomView.Room, 50, msgView.historyLoadPtr)
 	if err != nil {
 		roomView.AddServiceMessage("Failed to fetch history")
 		debug.Print("Failed to fetch history for", roomView.Room.ID, err)
 		view.parent.Render()
 		return
 	}
+	//debug.Printf("Load pointer %d -> %d", msgView.historyLoadPtr, newLoadPtr)
+	msgView.historyLoadPtr = newLoadPtr
 	for _, evt := range history {
 		roomView.AddHistoryEvent(evt)
 	}