Avoid unnecessary copies of AccessibilityChildrenVector

Source/modules/accessibility/AXNodeObject.cpp

Index: Source/modules/accessibility/AXNodeObject.cpp
diff --git a/Source/modules/accessibility/AXNodeObject.cpp b/Source/modules/accessibility/AXNodeObject.cpp
index 6110cb575101a3535a6844a711f1ade20e5928f9..40804da52f8d2c6a6e0a5e58750d7f9b6aee0bf3 100644
--- a/Source/modules/accessibility/AXNodeObject.cpp
+++ b/Source/modules/accessibility/AXNodeObject.cpp
@@ -1653,7 +1653,7 @@ void AXNodeObject::insertChild(AXObject* child, unsigned index)
     child->clearChildren();
 
     if (child->accessibilityIsIgnored()) {
-        AccessibilityChildrenVector children = child->children();
+        const AccessibilityChildrenVector& children = child->children();
         size_t length = children.size();
         for (size_t i = 0; i < length; ++i)
             m_children.insert(index + i, children[i]);