Add content renderer to the GN build

content/BUILD.gn

Index: content/BUILD.gn
diff --git a/content/BUILD.gn b/content/BUILD.gn
index 5768bafeb4bd6383a4cd1959d08c86754717f016..acdd32dd8b3c59fd77bbcb71959cbb03d53265da 100644
--- a/content/BUILD.gn
+++ b/content/BUILD.gn
@@ -2,6 +2,19 @@
 # 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" ]
+}
+
+grit("resources") {
+  source = "content_resources.grd"
+}
+
+# Stubs ------------------------------------------------------------------------
+
 # TODO(brettw) remove this and add a proper dependency on blink once that
 # target has been converted to GN. This config sets up the include directories
 # so content can compile in the meantime.
@@ -18,10 +31,13 @@ config("libjingle_stub_config") {
   include_dirs = [
     "//third_party/libjingle/overrides",
     "//third_party/libjingle/source",
-    "//third_party",
     "//third_party/libyuv/include",
     "//third_party/usrsctp",
+
+
+    "//third_party/webrtc/overrides",  # Must be before webrtc abd third_party.
     "//third_party/webrtc",
+    "//third_party",
   ]
 
   defines = [
@@ -51,3 +67,13 @@ config("libjingle_stub_config") {
   }
 }
 
+# This config is a placeholder to set up the V8 include path while the V8 GN
+# build is being worked on.
+config("v8_stub_config") {
+  include_dirs = [ "//v8/include" ]
+}
+
+config("widevine_stub_config") {
+  # The real implementation does a copy rule to copy the header to the gen dir.
+  include_dirs = [ "//third_party/widevine/cdm" ]
+}