DCHECK that paint properties are never null

third_party/WebKit/Source/web/tests/WebPluginContainerTest.cpp

 /*
  * Copyright (C) 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 716 matching lines @@
   runPendingTasks();
 
   WebPluginContainerImpl* container = static_cast<WebPluginContainerImpl*>(
       getWebPluginContainer(webView, WebString::fromUTF8("plugin")));
   ASSERT_TRUE(container);
   Element* element = static_cast<Element*>(container->element());
   const auto* plugin =
       static_cast<const CompositedPlugin*>(container->plugin());
 
   std::unique_ptr<PaintController> paintController = PaintController::create();
+  PaintChunkProperties properties;
+  properties.transform = TransformPaintPropertyNode::root();
+  properties.clip = ClipPaintPropertyNode::root();
+  properties.effect = EffectPaintPropertyNode::root();
+  properties.scroll = ScrollPaintPropertyNode::root();
+  paintController->updateCurrentPaintChunkProperties(nullptr, properties);
   GraphicsContext graphicsContext(*paintController);
   container->paint(graphicsContext, CullRect(IntRect(10, 10, 400, 300)));
   paintController->commitNewDisplayItems();
 
   const auto& displayItems =
       paintController->paintArtifact().getDisplayItemList();
   ASSERT_EQ(1u, displayItems.size());
   EXPECT_EQ(element->layoutObject(), &displayItems[0].client());
   ASSERT_EQ(DisplayItem::kForeignLayerPlugin, displayItems[0].getType());
   const auto& foreignLayerDisplayItem =
@@ skipping 20 matching lines @@
           WebString::fromUTF8("translated-plugin"));
   pluginContainerOneElement.pluginContainer()->setWantsWheelEvents(true);
 
   runPendingTasks();
   EXPECT_TRUE(
       webView->page()->frameHost().eventHandlerRegistry().hasEventHandlers(
           EventHandlerRegistry::WheelEventBlocking));
 }
 
 }  // namespace blink