Revert of Remove some ifdefs from ash since it only supports ChromeOS now.

ash/display/display_configuration_controller.cc

Index: ash/display/display_configuration_controller.cc
diff --git a/ash/display/display_configuration_controller.cc b/ash/display/display_configuration_controller.cc
index d65cdbb65af18f15bdb167f4f83d60da83399db5..1645345f98e1d20b29945dd4f78e530eeebd7a4d 100644
--- a/ash/display/display_configuration_controller.cc
+++ b/ash/display/display_configuration_controller.cc
@@ -5,15 +5,18 @@
 #include "ash/display/display_configuration_controller.h"
 
 #include "ash/display/display_animator.h"
-#include "ash/display/display_animator_chromeos.h"
 #include "ash/display/display_util.h"
 #include "ash/rotator/screen_rotation_animator.h"
 #include "base/time/time.h"
+#include "ui/display/display_layout.h"
+#include "ui/display/manager/display_manager.h"
+
+#if defined(OS_CHROMEOS)
+#include "ash/display/display_animator_chromeos.h"
 #include "chromeos/system/devicemode.h"
 #include "grit/ash_strings.h"
 #include "ui/base/l10n/l10n_util.h"
-#include "ui/display/display_layout.h"
-#include "ui/display/manager/display_manager.h"
+#endif
 
 namespace {
 
@@ -55,9 +58,11 @@
       window_tree_host_manager_(window_tree_host_manager),
       weak_ptr_factory_(this) {
   window_tree_host_manager_->AddObserver(this);
+#if defined(OS_CHROMEOS)
   if (chromeos::IsRunningAsSystemCompositor())
     limiter_.reset(new DisplayChangeLimiter);
   display_animator_.reset(new DisplayAnimatorChromeOS());
+#endif
 }
 
 DisplayConfigurationController::~DisplayConfigurationController() {
@@ -79,11 +84,13 @@
 void DisplayConfigurationController::SetMirrorMode(bool mirror,
                                                    bool user_action) {
   if (display_manager_->num_connected_displays() > 2) {
+#if defined(OS_CHROMEOS)
     if (user_action) {
       ShowDisplayErrorNotification(
           l10n_util::GetStringUTF16(IDS_ASH_DISPLAY_MIRRORING_NOT_SUPPORTED),
           false);
     }
+#endif
     return;
   }
   if (display_manager_->num_connected_displays() <= 1 ||