only re-show right panel if it was visible before we were mounted

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/components/views/rooms/ForwardMessage.js

@@ -55,9 +55,13 @@ module.exports = React.createClass({
 
     componentWillUnmount: function() {
         this._unmounted = true;
-        dis.dispatch({
-            action: 'show_right_panel',
-        });
+
+        if (!this.props.collapsedRhs) {
+            dis.dispatch({
+                action: 'show_right_panel',
+            });
+        }
+
         dis.dispatch({
             action: 'ui_opacity',
             sideOpacity: 1.0,