GN: Make content_shell and webkit_unit_tests work in component build

Except for webrtc, this produces content_shell and webkit_unit_tests
binaries that link and run successfully on linux.

[email protected]

Review URL: https://codereview.chromium.org/462983002

Cr-Commit-Position: refs/heads/master@{#289007}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@289007 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/content/BUILD.gn b/content/BUILD.gn
index a2bd48946..94c944d 100644
--- a/content/BUILD.gn
+++ b/content/BUILD.gn
@@ -14,7 +14,7 @@
   "//content/plugin",
   "//content/ppapi_plugin",
   "//content/public/app",
-  "//content/public/browser",
+  "//content/public/browser:sources",
   "//content/public/child",
   "//content/public/common",
   "//content/public/plugin",
@@ -28,6 +28,7 @@
     deps = content_shared_components + [
       "//content/app",
     ]
+    forward_dependent_configs_from = deps
   }
 } else {
   group("content") {