Move even more from WmShell to Shell

ash/system/chromeos/power/tablet_power_button_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/system/chromeos/power/tablet_power_button_controller.h"
 
 #include "ash/common/accessibility_delegate.h"
 #include "ash/common/session/session_controller.h"
 #include "ash/common/shell_delegate.h"
 #include "ash/common/wm/maximize_mode/maximize_mode_controller.h"
@@ skipping 25 matching lines @@
 constexpr int kIgnorePowerButtonAfterResumeMs = 2000;
 
 // Ignore button-up events occurring within this many milliseconds of the
 // previous button-up event. This prevents us from falling behind if the power
 // button is pressed repeatedly.
 constexpr int kIgnoreRepeatedButtonUpMs = 500;
 
 // Returns true if device is a convertible/tablet device, otherwise false.
 bool IsTabletModeSupported() {
   MaximizeModeController* maximize_mode_controller =
-      WmShell::Get()->maximize_mode_controller();
+      Shell::Get()->maximize_mode_controller();
   return maximize_mode_controller &&
          maximize_mode_controller->CanEnterMaximizeMode();
 }
 
 // Returns true if device is currently in tablet/maximize mode, otherwise false.
 bool IsTabletModeActive() {
   MaximizeModeController* maximize_mode_controller =
-      WmShell::Get()->maximize_mode_controller();
+      Shell::Get()->maximize_mode_controller();
   return maximize_mode_controller &&
          maximize_mode_controller->IsMaximizeModeWindowManagerEnabled();
 }
 
 }  // namespace
 
 TabletPowerButtonController::TestApi::TestApi(
     TabletPowerButtonController* controller)
     : controller_(controller) {}
 
@@ skipping 190 matching lines @@
   SessionController* session_controller = WmShell::Get()->session_controller();
   if (session_controller->ShouldLockScreenAutomatically() &&
       session_controller->CanLockScreen() &&
       !session_controller->IsUserSessionBlocked() &&
       !controller_->LockRequested()) {
     session_controller->LockScreen();
   }
 }
 
 }  // namespace ash