Add missing optional constructor param for Text

Author: alexeagle

baselines/dom.generated.d.ts

@@ -11583,6 +11583,7 @@ interface Text extends CharacterData {
     readonly wholeText: string;
     readonly assignedSlot: HTMLSlotElement | null;
     splitText(offset: number): Text;
+    new(data: string): Text;
 }
 
 declare var Text: {

inputfiles/addedTypes.json

@@ -1616,5 +1616,12 @@
             "name": "changedTouches?",
             "type": "Touch[]"
         }]
+    },
+    {
+        "kind": "interface",
+        "name": "Text",
+        "constructorSignatures": [
+            "new (data: string): Text"
+        ]
     }
 ]