Aura: Fix linux component build

ui/aura_shell/activation_controller.h

 // 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.
 
 #ifndef UI_AURA_SHELL_ACTIVATION_CONTROLLER_H_
 #define UI_AURA_SHELL_ACTIVATION_CONTROLLER_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/aura/client/activation_client.h"
 #include "ui/aura/root_window_observer.h"
 #include "ui/aura/window_observer.h"
+#include "ui/aura_shell/aura_shell_export.h"
 
 namespace aura_shell {
 namespace internal {
 
-class ActivationController : public aura::ActivationClient,
-                             public aura::WindowObserver,
-                             public aura::RootWindowObserver {
+// Exported for unit tests.
+class AURA_SHELL_EXPORT ActivationController : public aura::ActivationClient,
+                                               public aura::WindowObserver,
+                                               public aura::RootWindowObserver {
  public:
   ActivationController();
   virtual ~ActivationController();
 
   // Returns true if |window| exists within a container that supports
   // activation.
   static aura::Window* GetActivatableWindow(aura::Window* window);
 
   // Overridden from aura::ActivationClient:
   virtual void ActivateWindow(aura::Window* window) OVERRIDE;
@@ skipping 33 matching lines @@
   // tests to specify a default container.
   aura::Window* default_container_for_test_;
 
   DISALLOW_COPY_AND_ASSIGN(ActivationController);
 };
 
 }  // namespace internal
 }  // namespace aura_shell
 
 #endif  // UI_AURA_SHELL_ACTIVATION_CONTROLLER_H_