Get `gn gen` to succeed on Windows

ui/aura/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")
 
 component("aura") {
   sources = [
     "client/aura_constants.cc",
     "client/aura_constants.h",
@@ skipping 103 matching lines @@
     ]
     deps += [
       "//ui/events/platform/x11",
     ]
   }
 
   if (is_win) {
     sources -= [
       "input_state_lookup.cc",
     ]
-
-    deps += [
-      "//ui/metro_viewer",
-      "//ipc",
-    ]
   }
 
   if (use_ozone) {
     sources += [
       "window_tree_host_ozone.cc",
       "window_tree_host_ozone.h",
     ]
 
     # TODO(GYP) enable when these targets exist.
     #deps += [
@@ skipping 161 matching lines @@
   ]
 
   if (is_linux) {
     deps += [
       "//third_party/mesa",
     ]
   }
 }
 
 }  # if (false)