2nd display should show the same background as login/lock screen:

ash/desktop_background/desktop_background_component.cc

+// Copyright (c) 2012 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 "ash/desktop_background/desktop_background_component.h"
+
+#include "ui/aura/root_window.h"
+#include "ui/views/widget/widget.h"
+
+DECLARE_WINDOW_PROPERTY_TYPE(ash::internal::DesktopBackgroundComponent*);
+
+namespace ash {
+namespace internal {
+
+DEFINE_OWNED_WINDOW_PROPERTY_KEY(DesktopBackgroundComponent,
+                                 kWindowDesktopComponent, NULL);
+
+DesktopBackgroundComponent::DesktopBackgroundComponent(views::Widget* widget)
+    : widget_(widget) {
+}
+
+DesktopBackgroundComponent::DesktopBackgroundComponent(ui::Layer* layer)
+    : widget_(NULL) {
+  layer_.reset(layer);
+}
+
+
+DesktopBackgroundComponent::~DesktopBackgroundComponent() {
+  if (widget_) {
+    widget_->CloseNow();
+    widget_ = NULL;
+  }
+  if (layer_.get()) {

[Nikita (slow), 2012/07/25 20:45:24]

nit: no need for {}

[Denis Kuznetsov (DE-MUC), 2012/07/26 13:51:13]

Done.

+    layer_.reset(NULL);
+  }
+}
+
+void DesktopBackgroundComponent::SetBounds(gfx::Rect bounds) {
+  if (widget_)
+    widget_->SetBounds(bounds);
+  if (layer_.get())
+    layer_->SetBounds(bounds);
+}
+
+
+void DesktopBackgroundComponent::Reparent(aura::RootWindow* root_window ,

[sky, 2012/07/25 20:47:36]

remove white space

[Denis Kuznetsov (DE-MUC), 2012/07/26 13:51:13]

Done.

+                                          int src_container,
+                                          int dest_container) {
+  if (widget_) {
+    views::Widget::ReparentNativeView(widget_->GetNativeView(),
+        root_window->GetChildById(dest_container));
+  }
+  if (layer_.get()) {
+    ui::Layer* layer = layer_.get();
+    root_window->GetChildById(src_container)->layer()->Remove(layer);
+    root_window->GetChildById(dest_container)->layer()->Add(layer);
+  }
+}
+
+}  // namespace internal
+}  // namespace ash