Add chrome/browser/apps/BUILD.gn and move Chrome-specific code there

chrome/browser/apps/BUILD.gn

Index: chrome/browser/apps/BUILD.gn
diff --git a/chrome/browser/apps/BUILD.gn b/chrome/browser/apps/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..c56220320e10342d98c055aa41a71f19e8b91efa
--- /dev/null
+++ b/chrome/browser/apps/BUILD.gn
@@ -0,0 +1,56 @@
+# Copyright 2017 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("//extensions/features/features.gni")
+
+assert(enable_extensions)
+
+source_set("apps") {
+  sources = [
+    "app_launch_for_metro_restart_win.cc",
+    "app_launch_for_metro_restart_win.h",
+    "app_load_service.cc",
+    "app_load_service.h",
+    "app_load_service_factory.cc",
+    "app_load_service_factory.h",
+    "app_url_redirector.cc",
+    "app_url_redirector.h",
+    "app_window_registry_util.cc",
+    "app_window_registry_util.h",
+    "browser_context_keyed_service_factories.cc",
+    "browser_context_keyed_service_factories.h",
+    "install_chrome_app.cc",
+    "install_chrome_app.h",
+    "shortcut_manager.cc",
+    "shortcut_manager.h",
+    "shortcut_manager_factory.cc",
+    "shortcut_manager_factory.h",
+  ]
+
+  configs += [ "//build/config/compiler:wexit_time_destructors" ]
+
+  public_deps = [
+    "//apps",
+  ]
+
+  deps = [
+    "//chrome/app:command_ids",
+    "//chrome/browser/extensions",
+    "//chrome/browser/media/router/discovery",
+    "//chrome/common",
+    "//components/crx_file",
+    "//components/keyed_service/content",
+    "//components/navigation_interception",
+    "//components/pref_registry",
+    "//content/public/browser",
+    "//content/public/common",
+    "//extensions/browser",
+    "//extensions/common",
+    "//extensions/common/api",
+    "//net",
+    "//ui/gfx",
+  ]
+
+  allow_circular_includes_from = [ "//chrome/browser/extensions" ]
+}