[ios clean] Add placeholder for NTP bookmarks, chrome home and open tabs.

ios/clean/chrome/browser/ui/bookmarks/BUILD.gn

Index: ios/clean/chrome/browser/ui/bookmarks/BUILD.gn
diff --git a/ios/clean/chrome/browser/ui/bookmarks/BUILD.gn b/ios/clean/chrome/browser/ui/bookmarks/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..8892877892dd3efa665e8a95935ec6b63ab8c75d
--- /dev/null
+++ b/ios/clean/chrome/browser/ui/bookmarks/BUILD.gn
@@ -0,0 +1,20 @@
+# 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.
+
+source_set("bookmarks") {
+  sources = [
+    "bookmarks_coordinator.h",
+    "bookmarks_coordinator.mm",
+  ]
+
+  configs += [ "//build/config/compiler:enable_arc" ]
+
+  deps = [
+    "//ios/chrome/browser/ui:ui",
+    "//ios/chrome/browser/ui/bookmarks:bookmarks",
+    "//ios/shared/chrome/browser/coordinator_context",
+    "//ios/shared/chrome/browser/ui/browser_list:browser_list",
+    "//ios/shared/chrome/browser/ui/coordinators",
+  ]
+}