[Slimming Paint] Paint the inspector overlay with GraphicsLayer DisplayList.

Source/web/WebDevToolsAgentImpl.cpp

Index: Source/web/WebDevToolsAgentImpl.cpp
diff --git a/Source/web/WebDevToolsAgentImpl.cpp b/Source/web/WebDevToolsAgentImpl.cpp
index 48b05146305236edfd7c57d2e1e258a55013a011..f5d20c727ec586503c20f44fe56d327cc8efb7f5 100644
--- a/Source/web/WebDevToolsAgentImpl.cpp
+++ b/Source/web/WebDevToolsAgentImpl.cpp
@@ -486,28 +486,11 @@ LocalFrame* WebDevToolsAgentImpl::mainFrame()
     return 0;
 }
 
-// WebPageOverlay
-void WebDevToolsAgentImpl::paintPageOverlay(WebCanvas* canvas)
+// PageOverlay::Painter
+void WebDevToolsAgentImpl::paintPageOverlay(GraphicsContext& context)
 {
-    InspectorController* ic = inspectorController();
-    if (ic) {
-        OwnPtr<GraphicsContext> graphicsContext;
-        OwnPtr<DisplayItemList> displayItemList;
-        if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
-            displayItemList = DisplayItemList::create();
-            graphicsContext = adoptPtr(new GraphicsContext(nullptr, displayItemList.get()));
-        } else {
-            graphicsContext = adoptPtr(new GraphicsContext(canvas, nullptr));
-        }
-
-        graphicsContext->setCertainlyOpaque(false);
-        ic->drawHighlight(*graphicsContext);
-
-        if (RuntimeEnabledFeatures::slimmingPaintEnabled()) {
-            GraphicsContext context(canvas, nullptr);
-            displayItemList->replay(&context);
-        }
-    }
+    if (InspectorController* ic = inspectorController())
+        ic->drawHighlight(context);
 }
 
 void WebDevToolsAgentImpl::highlight()