[Cleanup] Factor out layout store code from DisplayController

ash/display/display_manager.cc

 // Copyright (c) 2012 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_manager.h"
 
 #include <cmath>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "ash/ash_switches.h"
 #include "ash/display/display_controller.h"
+#include "ash/display/display_layout_store.h"
 #include "ash/display/mirror_window_controller.h"
 #include "ash/screen_ash.h"
 #include "ash/shell.h"
 #include "base/auto_reset.h"
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "base/stl_util.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/stringprintf.h"
@@ skipping 106 matching lines @@
 
 using aura::RootWindow;
 using aura::Window;
 using std::string;
 using std::vector;
 
 DEFINE_WINDOW_PROPERTY_KEY(int64, kDisplayIdKey,
                            gfx::Display::kInvalidDisplayID);
 
 DisplayManager::DisplayManager()
-    : first_display_id_(gfx::Display::kInvalidDisplayID),
+    : layout_store_(new DisplayLayoutStore),
+      first_display_id_(gfx::Display::kInvalidDisplayID),
       num_connected_displays_(0),
       force_bounds_changed_(false),
       change_display_upon_host_resize_(false),
       software_mirroring_enabled_(false) {
 #if defined(OS_CHROMEOS)
   change_display_upon_host_resize_ = !base::chromeos::IsRunningOnChromeOS();
 #endif
   Init();
 }
 
@@ skipping 761 matching lines @@
   new_display.set_rotation(display_info.rotation());
   return new_display;
 }
 
 bool DisplayManager::UpdateSecondaryDisplayBoundsForLayout(
     DisplayList* displays,
     size_t* updated_index) const {
   if (displays->size() != 2U)
     return false;
 
-  DisplayController* controller = Shell::GetInstance()->display_controller();
   int64 id_at_zero = displays->at(0).id();
   DisplayIdPair pair =
       (id_at_zero == first_display_id_ ||
        id_at_zero == gfx::Display::InternalDisplayId()) ?
       std::make_pair(id_at_zero, displays->at(1).id()) :
       std::make_pair(displays->at(1).id(), id_at_zero) ;
   DisplayLayout layout =
-      controller->ComputeDisplayLayoutForDisplayIdPair(pair);
+      layout_store_->ComputeDisplayLayoutForDisplayIdPair(pair);
 
   // Ignore if a user has a old format (should be extremely rare)
   // and this will be replaced with DCHECK.
   if (layout.primary_id != gfx::Display::kInvalidDisplayID) {
     size_t primary_index, secondary_index;
     if (displays->at(0).id() == layout.primary_id) {
       primary_index = 0;
       secondary_index = 1;
     } else {
       primary_index = 1;
       secondary_index = 0;
     }
     gfx::Rect bounds =
         GetDisplayForId(displays->at(secondary_index).id()).bounds();
     UpdateDisplayBoundsForLayout(
         layout, displays->at(primary_index), &displays->at(secondary_index));
     *updated_index = secondary_index;
     return bounds != displays->at(secondary_index).bounds();
   }
   return false;
 }
 
 }  // namespace internal
 }  // namespace ash