C++ bindings: separate out serialization source set, have "mojom" targets optionally use serializat…

mojo/public/cpp/bindings/lib/message_validation.cc

+// 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.
+
+#include "mojo/public/cpp/bindings/lib/message_validation.h"
+
+#include "mojo/public/cpp/bindings/lib/validation_errors.h"
+#include "mojo/public/cpp/bindings/message.h"
+
+namespace mojo {
+namespace internal {
+
+bool ValidateMessageIsRequestWithoutResponse(const Message* message) {
+  if (message->has_flag(kMessageIsResponse) ||
+      message->has_flag(kMessageExpectsResponse)) {
+    ReportValidationError(VALIDATION_ERROR_MESSAGE_HEADER_INVALID_FLAGS);
+    return false;
+  }
+  return true;
+}
+
+bool ValidateMessageIsRequestExpectingResponse(const Message* message) {
+  if (message->has_flag(kMessageIsResponse) ||
+      !message->has_flag(kMessageExpectsResponse)) {
+    ReportValidationError(VALIDATION_ERROR_MESSAGE_HEADER_INVALID_FLAGS);
+    return false;
+  }
+  return true;
+}
+
+bool ValidateMessageIsResponse(const Message* message) {
+  if (message->has_flag(kMessageExpectsResponse) ||
+      !message->has_flag(kMessageIsResponse)) {
+    ReportValidationError(VALIDATION_ERROR_MESSAGE_HEADER_INVALID_FLAGS);
+    return false;
+  }
+  return true;
+}
+
+}  // namespace internal
+}  // namespace mojo