Fix qb tutorial link inside qb. Resolves #2940

frontend/src/metabase/query_builder/containers/QueryBuilder.jsx

@@ -67,6 +67,7 @@ const mapStateToProps = (state, props) => {
         updateUrl:                 props.updateUrl,
         user:                      state.currentUser,
         fromUrl:                   state.router && state.router.location && state.router.location.query.from,
+        location:                  state.router && state.router.location,
 
         card:                      card(state),
         originalCard:              originalCard(state),
@@ -128,6 +129,10 @@ export default class QueryBuilder extends Component {
             // ensure that some components are updated after the animation completes (e.g. card visualization)
             window.setTimeout(this.forceUpdateDebounced, 300);
         }
+        // HACK: if we switch to the tutorial from within the QB we need to manually re-initialize
+        if (!this.props.location.query.tutorial && nextProps.location.query.tutorial) {
+            this.props.initializeQB(nextProps.updateUrl);
+        }
     }
 
     componentWillUnmount() {