Reset room name hide timer if in an unnamed room

This avoids the room name awkwardly moving back up if the cursor is at
the bottom of the screen in a room with a room name, then the user
switches to a room without a room name, then moves the cursor away from
the bottom, then switches to a named room - even though the cursor was
already away from the bottom of the screen.

Conversely, if the user moves their cursor to the bottom of the screen
in an unnamed room, then switches into a named room, the room name will
already have been hidden and they won't need to wait for it to hide.

desktop_version/src/editor.cpp

@@ -3628,6 +3628,17 @@ void editorrenderfixed(void)
             }
         }
     }
+    else
+    {
+        if (ed.tiley < 28)
+        {
+            ed.roomnamehide = 0;
+        }
+        else
+        {
+            ed.roomnamehide = 12;
+        }
+    }
 }
 
 void editorlogic(void)