Ensure the permissions DOMTokenList is initialized before access

third_party/WebKit/Source/core/html/HTMLIFrameElementTest.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/html/HTMLIFrameElement.h"
 
 #include "core/dom/Document.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blink {
 
+// Test setting via the Element attribute (HTML codepath).
 TEST(HTMLIFrameElementTest, SetPermissionsAttribute)
 {
     Document* document = Document::create();
     HTMLIFrameElement* iframe = HTMLIFrameElement::create(*document);
 
-    // Test setting via the Element attribute (HTML codepath).
     iframe->setAttribute(HTMLNames::permissionsAttr, "geolocation");
     EXPECT_EQ("geolocation", iframe->permissions()->value());
     iframe->setAttribute(HTMLNames::permissionsAttr, "geolocation notifications");
     EXPECT_EQ("geolocation notifications", iframe->permissions()->value());
+}
 
-    // Test setting via the DOMTokenList (JS codepath).
+// Test setting via the DOMTokenList (JS codepath).
+TEST(HTMLIFrameElementTest, SetPermissionsAttributeJS)
+{
+    Document* document = Document::create();
+    HTMLIFrameElement* iframe = HTMLIFrameElement::create(*document);
+
     iframe->permissions()->setValue("midi");
     EXPECT_EQ("midi", iframe->getAttribute(HTMLNames::permissionsAttr));
 }
 
 } // namespace blink