Make content_shell link in the GN build.

content/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("//tools/grit/grit_rule.gni")
 
 # Applied by targets internal to content.
 config("content_implementation") {
   defines = [ "CONTENT_IMPLEMENTATION" ]
 }
 
-content_components = [
-  "//content/app",
-  "//content/browser",
-  "//content/child",
+content_shared_components = [
   "//content/gpu",
   "//content/plugin",
   "//content/ppapi_plugin",
   "//content/public/app",
   "//content/public/browser",
   "//content/public/child",
+  "//content/public/common",
   "//content/public/plugin",
   "//content/public/renderer",
   "//content/renderer",
   "//content/utility",
 ]
 
 if (is_component_build) {
   shared_library("content") {
-    deps = content_components
+    deps = content_shared_components + [
+      "//content/app",
+    ]
   }
 } else {
   group("content") {
-    deps = content_components
+    deps = content_shared_components
   }
 }
 
 grit("resources") {
   source = "content_resources.grd"
   outputs = [
     "grit/content_resources.h",
     "content_resources.pak",
     "content_resources.rc",
   ]
@@ skipping 75 matching lines @@
     import("//build/config/crypto.gni")
     if (use_openssl) {
       defines += [ "WEBRTC_ANDROID_OPENSLEQS" ]
     }
   }
 
   if (is_posix) {
     defines += [ "WEBRTC_POSIX" ]
   }
 }