Make more of content pass "gn check"

content/common/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/features.gni")
 import("//build/config/ui.gni")
 import("//content/common/common.gni")
 import("//media/media_options.gni")
 import("//mojo/public/tools/bindings/mojom.gni")
 if (is_mac) {
@@ skipping 168 matching lines @@
     "//mojo/shell/public/interfaces",
     "//mojo/shell/runner/common",
     "//net",
     "//sandbox",
     "//skia",
     "//storage/common",
     "//third_party/WebKit/public:blink",
     "//third_party/boringssl",
     "//third_party/icu",
     "//third_party/libjingle",
+    "//third_party/webrtc/base:rtc_base",
     "//ui/accessibility",
     "//ui/base",
     "//ui/base/ime",
     "//ui/events/ipc:events_ipc",
     "//ui/gfx",
     "//ui/gfx/geometry",
     "//ui/gfx/ipc",
     "//ui/gl",
     "//ui/shell_dialogs",
     "//url",
@@ skipping 338 matching lines @@
   public_deps = [
     "//components/leveldb/public/interfaces",
     "//components/mus/public/interfaces",
     "//content/public/common:mojo_bindings",
     "//mojo/shell/public/interfaces",
     "//skia/public/interfaces",
     "//third_party/WebKit/public:mojo_bindings",
     "//ui/mojo/geometry:interfaces",
   ]
 }