CrOS Tablet Window management - Split Screen part I

ash/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/base/ui_features.gni")
 
 # Historical note: Ash shipped on Windows for a couple years to support
@@ skipping 674 matching lines @@
     "wm/maximize_mode/scoped_disable_internal_mouse_and_keyboard_ozone.h",
     "wm/maximize_mode/scoped_disable_internal_mouse_and_keyboard_x11.cc",
     "wm/maximize_mode/scoped_disable_internal_mouse_and_keyboard_x11.h",
     "wm/mru_window_tracker.cc",
     "wm/mru_window_tracker.h",
     "wm/overlay_event_filter.cc",
     "wm/overlay_event_filter.h",
     "wm/overview/cleanup_animation_observer.cc",
     "wm/overview/cleanup_animation_observer.h",
     "wm/overview/overview_animation_type.h",
+    "wm/overview/overview_window_drag_controller.cc",
+    "wm/overview/overview_window_drag_controller.h",
     "wm/overview/scoped_overview_animation_settings.cc",
     "wm/overview/scoped_overview_animation_settings.h",
     "wm/overview/scoped_transform_overview_window.cc",
     "wm/overview/scoped_transform_overview_window.h",
     "wm/overview/window_grid.cc",
     "wm/overview/window_grid.h",
     "wm/overview/window_selector.cc",
     "wm/overview/window_selector.h",
     "wm/overview/window_selector_controller.cc",
     "wm/overview/window_selector_controller.h",
@@ skipping 23 matching lines @@
     "wm/root_window_layout_manager.cc",
     "wm/root_window_layout_manager.h",
     "wm/screen_dimmer.cc",
     "wm/screen_dimmer.h",
     "wm/screen_pinning_controller.cc",
     "wm/screen_pinning_controller.h",
     "wm/session_state_animator.cc",
     "wm/session_state_animator.h",
     "wm/session_state_animator_impl.cc",
     "wm/session_state_animator_impl.h",
+    "wm/splitview/split_view_controller.cc",
+    "wm/splitview/split_view_controller.h",
     "wm/stacking_controller.cc",
     "wm/stacking_controller.h",
     "wm/switchable_windows.cc",
     "wm/switchable_windows.h",
     "wm/system_gesture_event_filter.cc",
     "wm/system_gesture_event_filter.h",
     "wm/system_modal_container_event_filter.cc",
     "wm/system_modal_container_event_filter.h",
     "wm/system_modal_container_event_filter_delegate.h",
     "wm/system_modal_container_layout_manager.cc",
@@ skipping 777 matching lines @@
     "//content/public/app:both",
     "//device/bluetooth",
   ]
 
   data_deps = [
     "//ash/strings:ash_test_strings",
     "//ash/resources:ash_test_resources_with_content_100_percent",
     "//ash/resources:ash_test_resources_200_percent",
   ]
 }