aura: A few changes to have aura_demo compile and run on linux.

aura/demo/demo_main.cc

 // Copyright (c) 2011 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 "aura/desktop.h"
 #include "aura/event.h"
 #include "aura/window.h"
 #include "aura/window_delegate.h"
 #include "base/at_exit.h"
 #include "base/command_line.h"
 #include "base/i18n/icu_util.h"
 #include "base/memory/scoped_ptr.h"
 #include "third_party/skia/include/core/SkXfermode.h"
 #include "ui/base/resource/resource_bundle.h"
 #include "ui/base/ui_base_paths.h"
 #include "ui/gfx/canvas_skia.h"
 #include "ui/gfx/rect.h"
 
+#if defined(USE_X11)
+#include "aura/hit_test.h"
+#include "base/message_pump_x.h"
+#endif
+
 namespace {
 
 // Trivial WindowDelegate implementation that draws a colored background.
 class DemoWindowDelegate : public aura::WindowDelegate {
  public:
   explicit DemoWindowDelegate(SkColor color) : color_(color) {}
 
   virtual void OnFocus() OVERRIDE {}
   virtual void OnBlur() OVERRIDE {}
   virtual bool OnKeyEvent(aura::KeyEvent* event) OVERRIDE {
@@ skipping 62 matching lines @@
   window3.set_id(3);
   window3.Init();
   window3.SetBounds(gfx::Rect(10, 10, 50, 50), 0);
   window3.SetVisibility(aura::Window::VISIBILITY_SHOWN);
   window3.SetParent(&window2);
 
   aura::Desktop::GetInstance()->Run();
   return 0;
 }