Add support for sending protobuf messages over IPC.

chrome/common/safe_browsing/ipc_protobuf_message_null_macros.h

Index: chrome/common/safe_browsing/ipc_protobuf_message_null_macros.h
diff --git a/chrome/common/safe_browsing/ipc_protobuf_message_null_macros.h b/chrome/common/safe_browsing/ipc_protobuf_message_null_macros.h
new file mode 100644
index 0000000000000000000000000000000000000000..ffb7fe0f4339e132b406a15b2ac33c5b7f5c463d
--- /dev/null
+++ b/chrome/common/safe_browsing/ipc_protobuf_message_null_macros.h
@@ -0,0 +1,19 @@
+// Copyright 2015 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.
+
+// No include guard, may be included multiple times.
+
+// NULL out all the macros that need NULLing, so that multiple includes of
+// *_generator.h files will not generate noise.
+#undef IPC_PROTOBUF_MESSAGE_TRAITS_BEGIN
+#undef IPC_PROTOBUF_MESSAGE_TRAITS_OPTIONAL_FUNDAMENTAL_MEMBER
+#undef IPC_PROTOBUF_MESSAGE_TRAITS_OPTIONAL_COMPLEX_MEMBER
+#undef IPC_PROTOBUF_MESSAGE_TRAITS_REPEATED_COMPLEX_MEMBER
+#undef IPC_PROTOBUF_MESSAGE_TRAITS_END
+
+#define IPC_PROTOBUF_MESSAGE_TRAITS_BEGIN(message_name)
+#define IPC_PROTOBUF_MESSAGE_TRAITS_OPTIONAL_FUNDAMENTAL_MEMBER(name)
+#define IPC_PROTOBUF_MESSAGE_TRAITS_OPTIONAL_COMPLEX_MEMBER(name)
+#define IPC_PROTOBUF_MESSAGE_TRAITS_REPEATED_COMPLEX_MEMBER(name)
+#define IPC_PROTOBUF_MESSAGE_TRAITS_END()