add shift into delete action (#7274)

* add shift into delete action

* add change file

* Delete yarn.lock

* modify change file

* Update add-shift-into-delete-action_2018-11-30-21-46.json

* add checks for setSeleted in suggestionscore

common/changes/office-ui-fabric-react/add-shift-into-delete-action_2018-11-30-21-46.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "packageName": "office-ui-fabric-react",
+      "comment": "Picker: The shift key is now required (in addition to the del key) in order to delete a suggestion.",
+      "type": "patch"
+    }
+  ],
+  "packageName": "office-ui-fabric-react",
+  "email": "[email protected]"
+}

packages/office-ui-fabric-react/src/components/FloatingPicker/BaseFloatingPicker.tsx

@@ -266,14 +266,15 @@ export class BaseFloatingPicker<T, P extends IBaseFloatingPickerProps<T>> extend
           this.props.onRemoveSuggestion &&
           this.suggestionsControl &&
           this.suggestionsControl.hasSuggestionSelected &&
-          this.suggestionsControl.currentSuggestion
+          this.suggestionsControl.currentSuggestion &&
+          ev.shiftKey
         ) {
           (this.props.onRemoveSuggestion as ((item: T) => void))(this.suggestionsControl.currentSuggestion!.item);
 
           this.suggestionsControl.removeSuggestion();
           this.forceUpdate();
+          ev.stopPropagation();
         }
-        ev.stopPropagation();
         break;
 
       case KeyCodes.up:

packages/office-ui-fabric-react/src/components/FloatingPicker/Suggestions/SuggestionsCore.tsx

@@ -103,7 +103,7 @@ export class SuggestionsCore<T> extends BaseComponent<ISuggestionsCoreProps<T>,
       this.currentSuggestion = suggestions[0];
       this.currentSuggestion.selected = true;
     } else {
-      if (this.currentIndex > -1) {
+      if (this.currentIndex > -1 && suggestions[this.currentIndex]) {
         suggestions[this.currentIndex].selected = false;
       }
       suggestions[index].selected = true;