Linux Aura: Use managed tab dragging when possible (Reland)

ui/views/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 import("//ui/ozone/ozone.gni")
 
 config("flags") {
@@ skipping 558 matching lines @@
           "widget/desktop_aura/desktop_drag_drop_client_aurax11.h",
           "widget/desktop_aura/desktop_screen_x11.cc",
           "widget/desktop_aura/desktop_screen_x11.h",
           "widget/desktop_aura/desktop_window_tree_host_x11.cc",
           "widget/desktop_aura/desktop_window_tree_host_x11.h",
           "widget/desktop_aura/x11_desktop_handler.cc",
           "widget/desktop_aura/x11_desktop_handler.h",
           "widget/desktop_aura/x11_desktop_handler_observer.h",
           "widget/desktop_aura/x11_desktop_window_move_client.cc",
           "widget/desktop_aura/x11_desktop_window_move_client.h",
+          "widget/desktop_aura/x11_desktop_window_move_client_managed.cc",
+          "widget/desktop_aura/x11_desktop_window_move_client_managed.h",
           "widget/desktop_aura/x11_move_loop.h",
           "widget/desktop_aura/x11_move_loop_delegate.h",
           "widget/desktop_aura/x11_pointer_grab.cc",
           "widget/desktop_aura/x11_pointer_grab.h",
           "widget/desktop_aura/x11_topmost_window_finder.cc",
           "widget/desktop_aura/x11_topmost_window_finder.h",
           "widget/desktop_aura/x11_whole_screen_move_loop.cc",
           "widget/desktop_aura/x11_whole_screen_move_loop.h",
           "widget/desktop_aura/x11_window_event_filter.cc",
           "widget/desktop_aura/x11_window_event_filter.h",
@@ skipping 420 matching lines @@
       "//ui/base:test_support",
       "//ui/compositor",
       "//ui/events:test_support",
       "//ui/gl:test_support",
       "//ui/resources",
       "//ui/resources:ui_test_pak",
       "//ui/strings",
     ]
   }
 }