Fixed the ScreenOrientationController so that it doesn't crash by animating

ash/rotator/screen_rotation_animator.cc

 // Copyright 2015 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/rotator/screen_rotation_animator.h"
 
 #include <string>
 #include <vector>
 
 #include "ash/ash_switches.h"
@@ skipping 249 matching lines @@
 
 }  // namespace
 
 ScreenRotationAnimator::ScreenRotationAnimator(int64 display_id)
     : display_id_(display_id) {
 }
 
 ScreenRotationAnimator::~ScreenRotationAnimator() {
 }
 
+bool ScreenRotationAnimator::CanAnimate() const {
+  return Shell::GetInstance()
+      ->display_manager()
+      ->GetDisplayForId(display_id_)
+      .is_valid();
+}
+
 void ScreenRotationAnimator::Rotate(gfx::Display::Rotation new_rotation) {
   const gfx::Display::Rotation current_rotation =
       GetCurrentRotation(display_id_);
 
   if (current_rotation == new_rotation)
     return;
 
   const std::string switch_value =
       base::CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
           switches::kAshEnableScreenRotationAnimation);
@@ skipping 19 matching lines @@
     RotateScreen(display_id_, new_rotation,
                  base::TimeDelta::FromMilliseconds(kRotationDurationInMs),
                  rotation_degrees, 0 /* rotation_degree_offset */,
                  gfx::Tween::FAST_OUT_LINEAR_IN, true /* should_scale */);
   } else {
     NOTREACHED();
   }
 }
 
 }  // namespace ash