Work on blink GN bindings

Source/bindings/modules/v8/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("//third_party/WebKit/Source/bindings/modules/v8/generated.gni")
+import("//third_party/WebKit/Source/bindings/scripts/scripts.gni")
+import("//third_party/WebKit/Source/modules/modules.gni")
+
+# bindings_modules_generated in modules/v8/generated.gyp
+group("bindings_modules_generated") {
+  deps = [
+    ":bindings_modules_generated_aggregate",
+    ":bindings_modules_generated_individual",
+  ]
+}
+
+# bindings_modules_generated_aggregate in modules/v8/generated.gyp
+aggregate_generated_bindings("bindings_modules_generated_aggregate") {
+  sources = modules_idl_files
+  component_dir = "modules"
+  outputs = bindings_modules_generated_aggregate_files
+}
+
+# bindings_modules_generated_individual in modules/v8/generated.gyp
+idl_compiler("bindings_modules_generated_individual") {
+  # Note in GYP this is modules_interface_idl_files but this variable is just
+  # defined to modules_idl_files.
+  sources = modules_idl_files
+  output_dir = bindings_modules_v8_output_dir
+}