Add a few new node defines

electron.gyp

@@ -207,6 +207,9 @@
         'vendor/node/node.gyp:node',
       ],
       'defines': [
+        # We need to access internal implementations of Node.
+        'NODE_WANT_INTERNALS=1',
+        'NODE_SHARED_MODE',
         # This is defined in skia/skia_common.gypi.
         'SK_SUPPORT_LEGACY_GETTOPDEVICE',
         # Disable warnings for g_settings_list_schemas.