Added null check for value in getFieldFromDoc, closes #8027

Author: lucidNTR

packages/node_modules/pouchdb-selector-core/src/utils.js

@@ -3,6 +3,9 @@ import { clone } from 'pouchdb-utils';
 // this would just be "return doc[field]", but fields
 // can be "deep" due to dot notation
 function getFieldFromDoc(doc, parsedField) {
+  if (!doc) {
+    return;
+  }
   var value = doc;
   for (var i = 0, len = parsedField.length; i < len; i++) {
     var key = parsedField[i];