Fix import

Author: tom-andersen

firebase-firestore/src/test/java/com/google/firebase/firestore/local/LocalStoreTestCase.java

@@ -20,6 +20,7 @@
 import static com.google.firebase.firestore.testutil.TestUtil.deleteMutation;
 import static com.google.firebase.firestore.testutil.TestUtil.deletedDoc;
 import static com.google.firebase.firestore.testutil.TestUtil.doc;
+import static com.google.firebase.firestore.testutil.TestUtil.docMap;
 import static com.google.firebase.firestore.testutil.TestUtil.existenceFilterEvent;
 import static com.google.firebase.firestore.testutil.TestUtil.filter;
 import static com.google.firebase.firestore.testutil.TestUtil.key;