Add GN "resources" target for blink_resources GYP target.

public/BUILD.gn

Index: public/BUILD.gn
diff --git a/public/BUILD.gn b/public/BUILD.gn
index 536bfa2ffe39a203fbcb56f59b2092e77f3788a7..73183ec6db5d708c2abbaf19bf88e96539d5f0e4 100644
--- a/public/BUILD.gn
+++ b/public/BUILD.gn
@@ -2,6 +2,8 @@
 # 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")
+
 if (!is_android) {
 
 # GYP version: WebKit/public/blink.gyp:blink
@@ -73,3 +75,12 @@ group("blink_generate_devtools_grd") {
     "//third_party/WebKit/Source/devtools:generate_devtools_grd",
   ]
 }
+
+grit("resources") {
+  source = "blink_resources.grd"
+  outputs = [
+    "grit/blink_resources.h",
+    "blink_resources.rc",
+    "blink_resources.pak",
+  ]
+}