Call ShowRootWindow on NativeWindow's RootWindow to display the window.

content/shell/shell.cc

Index: content/shell/shell.cc
diff --git a/content/shell/shell.cc b/content/shell/shell.cc
index ce7e8f41a7e7243a7dcd455acaf3c15aaf34775a..664554e517df77a63da7e3ddc527edf180f47308 100644
--- a/content/shell/shell.cc
+++ b/content/shell/shell.cc
@@ -126,6 +126,11 @@ Shell* Shell::FromRenderViewHost(RenderViewHost* rvh) {
   return NULL;
 }
 
+// static
+void Shell::Initialize() {
+  PlatformInitialize(gfx::Size(kTestWindowWidth, kTestWindowHeight));
+}
+
 Shell* Shell::CreateNewWindow(BrowserContext* browser_context,
                               const GURL& url,
                               SiteInstance* site_instance,