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

ui/wm/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/ui.gni")
 import("//testing/test.gni")
 
 component("wm") {
   sources = [
     "core/accelerator_delegate.h",
@@ skipping 67 matching lines @@
     "//ui/events/devices",
     "//ui/events/platform",
     "//ui/events/platform",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/resources",
   ]
 
   if (use_x11) {
     configs += [ "//build/config/linux:x11" ]
+    deps += [ "//ui/events/devices/x11" ]
   }
 }
 
 static_library("test_support") {
   testonly = true
   sources = [
     "test/wm_test_helper.cc",
     "test/wm_test_helper.h",
   ]
 
@@ skipping 42 matching lines @@
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/gl:test_support",
     "//ui/resources",
   ]
 
   data_deps = [
     "//ui/resources:ui_test_pak_data",
   ]
 }