IndexedDB: Replace O(n^2) algorithm computing multientry index keys

third_party/WebKit/Source/modules/indexeddb/IDBObjectStore.cpp

Index: third_party/WebKit/Source/modules/indexeddb/IDBObjectStore.cpp
diff --git a/third_party/WebKit/Source/modules/indexeddb/IDBObjectStore.cpp b/third_party/WebKit/Source/modules/indexeddb/IDBObjectStore.cpp
index 8ca3177513f2d504be24887d9d42b37c5816514c..96b02148a7c520b30ee39d87f801adb3c658f26c 100644
--- a/third_party/WebKit/Source/modules/indexeddb/IDBObjectStore.cpp
+++ b/third_party/WebKit/Source/modules/indexeddb/IDBObjectStore.cpp
@@ -329,10 +329,7 @@ static void generateIndexKeysForValue(v8::Isolate* isolate,
   } else {
     DCHECK(indexMetadata.multiEntry);
     DCHECK_EQ(indexKey->getType(), IDBKey::ArrayType);
-    indexKey = IDBKey::createMultiEntryArray(indexKey->array());
-
-    for (size_t i = 0; i < indexKey->array().size(); ++i)
-      indexKeys->push_back(indexKey->array()[i]);
+    indexKeys->appendVector(indexKey->toMultiEntryArray());
   }
 }