Fix crash reported by the PlayStore, for release 1.3.4

I did not find a way to reproduce, but this change should add some safety

vector/src/main/java/im/vector/app/features/home/room/detail/RoomDetailFragment.kt

@@ -641,11 +641,13 @@ class RoomDetailFragment @Inject constructor(
                     }
                 }
                 .setOnEmojiPopupDismissListener {
+                    if (isAdded) {
                         views.composerLayout.views.composerEmojiButton.apply {
                             contentDescription = getString(R.string.a11y_open_emoji_picker)
                             setImageResource(R.drawable.ic_insert_emoji)
                         }
                     }
+                }
                 .build(views.composerLayout.views.composerEditText)
     }