Clarify comment (#455)

imgui_demo.cpp

@@ -1972,7 +1972,7 @@ struct ExampleAppConsole
 
         // Demonstrate keeping auto focus on the input box
         if (ImGui::IsItemHovered() || (ImGui::IsRootWindowOrAnyChildFocused() && !ImGui::IsAnyItemActive() && !ImGui::IsMouseClicked(0)))
-            ImGui::SetKeyboardFocusHere(-1); // Auto focus
+            ImGui::SetKeyboardFocusHere(-1); // Auto focus previous widget
 
         ImGui::End();
     }