videoview: move conversation connection to callwidget

Fixes crash when no accounts are available, and reconnects signal
when account changes.

Change-Id: I3b71411bf3493c7831071c51c0b0d3fa30e92f76
diff --git a/videoview.h b/videoview.h
index ec71e88..f2f388c 100644
--- a/videoview.h
+++ b/videoview.h
@@ -43,6 +43,7 @@
     ~VideoView();
     void pushRenderer(const std::string& callUid);
     void showChatviewIfToggled();
+    void simulateShowChatview(bool checked);
 
 protected:
     void resizeEvent(QResizeEvent* event);