Split //ui/events/devices into two targets.

ui/base/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/buildflag_header.gni")
 import("//build/config/compiler/compiler.gni")
 import("//build/config/sanitizers/sanitizers.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 import("//ui/base/ui_features.gni")
@@ skipping 394 matching lines @@
 
   if (use_aura) {
     deps += [ "//ui/events" ]
   } else {
     sources -= [
       "cursor/cursor.cc",
       "cursor/cursor.h",
       "dragdrop/drag_utils_aura.cc",
     ]
   }
+
+  # TODO(kylechar): remove ozone_platform_x11 from here.
   if (use_x11 || ozone_platform_x11) {
     sources += [
       "x/x11_foreign_window_manager.cc",
       "x/x11_foreign_window_manager.h",
       "x/x11_menu_list.cc",
       "x/x11_menu_list.h",
       "x/x11_util.cc",
       "x/x11_util.h",
       "x/x11_util_internal.h",
     ]
     if (!is_chromeos) {
       sources += [
         "idle/idle_query_x11.cc",
         "idle/idle_query_x11.h",
         "idle/screensaver_window_finder_x11.cc",
         "idle/screensaver_window_finder_x11.h",
       ]
       configs += [ "//build/config/linux:xscrnsaver" ]
     }
-    deps += [ "//ui/gfx/x" ]
+    deps += [
+      "//ui/events/devices/x11",
+      "//ui/gfx/x",
+    ]
   }
 
   if (!use_aura || !is_linux) {
     sources -= [ "resource/resource_bundle_auralinux.cc" ]
   }
 
   if (use_aura && is_win) {
     sources -= [ "dragdrop/drag_utils_aura.cc" ]
   }
 
@@ skipping 511 matching lines @@
 if (is_mac) {
   mac_framework_bundle("ui_unittests_framework") {
     testonly = true
     deps = [
       "//ui/resources:ui_test_pak_bundle_data",
     ]
     info_plist = "test/framework-Info.plist"
     output_name = "ui_unittests Framework"
   }
 }