Remove MouseWarpController construction from ash::DisplayManager

ash/display/display_manager.cc

Index: ash/display/display_manager.cc
diff --git a/ash/display/display_manager.cc b/ash/display/display_manager.cc
index a540a38e7ea9e94a4fcdc2036f8896f4036be141..e99e65673d84c3b8aaea6214bd59c9c2ad88bdc9 100644
--- a/ash/display/display_manager.cc
+++ b/ash/display/display_manager.cc
@@ -15,10 +15,7 @@
 
 #include "ash/common/ash_switches.h"
 #include "ash/display/display_util.h"
-#include "ash/display/extended_mouse_warp_controller.h"
-#include "ash/display/null_mouse_warp_controller.h"
 #include "ash/display/screen_ash.h"
-#include "ash/display/unified_mouse_warp_controller.h"
 #include "ash/screen_util.h"
 #include "ash/shell.h"
 #include "base/auto_reset.h"
@@ -1071,17 +1068,6 @@ void DisplayManager::CreateMirrorWindowAsyncIfAny() {
                             weak_ptr_factory_.GetWeakPtr()));
 }
 
-std::unique_ptr<MouseWarpController> DisplayManager::CreateMouseWarpController(
-    aura::Window* drag_source) const {
-  if (IsInUnifiedMode() && num_connected_displays() >= 2)
-    return base::MakeUnique<UnifiedMouseWarpController>();
-  // Extra check for |num_connected_displays()| is for SystemDisplayApiTest
-  // that injects MockScreen.
-  if (GetNumDisplays() < 2 || num_connected_displays() < 2)
-    return base::MakeUnique<NullMouseWarpController>();
-  return base::MakeUnique<ExtendedMouseWarpController>(drag_source);
-}
-
 void DisplayManager::CreateScreenForShutdown() const {
   delete screen_for_shutdown;
   screen_for_shutdown = screen_->CloneForShutdown();