Add more components to "gn check", work on dom_distiller.

components/dom_distiller/content/common/BUILD.gn

+# Copyright 2015 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("//mojo/public/tools/bindings/mojom.gni")
+
+# GYP version: components/dom_distiller.gypi:dom_distiller_content_common
+source_set("common") {
+  sources = [
+    "distiller_messages.cc",
+    "distiller_messages.h",
+  ]
+
+  deps = [
+    "//base",
+    "//content/public/common",
+    "//ipc",
+    "//url",
+  ]
+}
+
+# GYP version: components/dom_distiller.gypi:dom_distiller_mojo_bindings
+mojom("mojo_bindings") {
+  sources = [
+    "distiller_javascript_service.mojom",
+    "distiller_page_notifier_service.mojom",
+  ]
+}