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 d4e68c04fa2d1dfecdb70af50e5d85e836a20472..b33f29bf32f9e121a992540933131296211f991e 100644
--- a/content/shell/shell.cc
+++ b/content/shell/shell.cc
@@ -30,9 +30,9 @@
 #include "content/shell/shell_switches.h"
 #include "content/shell/webkit_test_controller.h"
 
-// Content area size for newly created windows.
-static const int kTestWindowWidth = 800;
-static const int kTestWindowHeight = 600;
+#if defined(USE_AURA)
+#include "content/shell/shell_stacking_client_ash.h"
+#endif
 
 namespace content {
 
@@ -127,6 +127,7 @@ Shell* Shell::CreateNewWindow(BrowserContext* browser_context,
     create_params.initial_size = initial_size;
   else
     create_params.initial_size = gfx::Size(kTestWindowWidth, kTestWindowHeight);
+  create_params.context = Shell::stacking_client_->GetDefaultParent(NULL, NULL, gfx::Rect());

[Nayan, 2013/01/15 23:39:03]

Done.

   WebContents* web_contents = WebContents::Create(create_params);
   Shell* shell = CreateShell(web_contents);
   if (!url.is_empty())