Detect and fix overlapping displays

ash/display/display_configuration_controller.cc

 // Copyright 2016 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/display/display_configuration_controller.h"
 
 #include "ash/display/display_animator.h"
 #include "ash/display/display_util.h"
 #include "ash/rotator/screen_rotation_animator.h"
 #include "base/time/time.h"
@@ skipping 142 matching lines @@
   if (limiter_)
     limiter_->SetThrottleTimeout(throttle_ms);
 }
 
 bool DisplayConfigurationController::IsLimited() {
   return limiter_ && limiter_->IsThrottled();
 }
 
 void DisplayConfigurationController::SetDisplayLayoutImpl(
     std::unique_ptr<display::DisplayLayout> layout) {
-  // TODO(oshima/stevenjb): Add support for 3+ displays.
   display_manager_->SetLayoutForCurrentDisplays(std::move(layout));
   if (display_animator_)
     display_animator_->StartFadeInAnimation();
 }
 
 void DisplayConfigurationController::SetMirrorModeImpl(bool mirror) {
   display_manager_->SetMirrorMode(mirror);
   if (display_animator_)
     display_animator_->StartFadeInAnimation();
 }
 
 void DisplayConfigurationController::SetPrimaryDisplayIdImpl(
     int64_t display_id) {
   window_tree_host_manager_->SetPrimaryDisplayId(display_id);
   if (display_animator_)
     display_animator_->StartFadeInAnimation();
 }
 
 }  // namespace ash