Make IPC_MESSAGE_EXPORT more robust.

ipc/ipc_message.h

 // Copyright (c) 2011 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.
 
 #ifndef IPC_IPC_MESSAGE_H_
 #define IPC_IPC_MESSAGE_H_
 #pragma once
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/pickle.h"
 #include "ipc/ipc_export.h"
 
-#ifndef NDEBUG
+// Ipc logging adds a dependency from the 'chrome' target on all ipc message
+// classes. In a component build, this would require exporting all message
+// classes, so don't support ipc logging in the components build.
+#if !defined(NDEBUG) && !defined(COMPONENT_BUILD)
 #define IPC_MESSAGE_LOG_ENABLED
 #endif
 
 #if defined(OS_POSIX)
 #include "base/memory/ref_counted.h"
 #endif
 
 namespace base {
 struct FileDescriptor;
 }
@@ skipping 249 matching lines @@
   MSG_ROUTING_NONE = -2,
 
   // indicates a general message not sent to a particular tab.
   MSG_ROUTING_CONTROL = kint32max,
 };
 
 #define IPC_REPLY_ID 0xFFFFFFF0  // Special message id for replies
 #define IPC_LOGGING_ID 0xFFFFFFF1  // Special message id for logging
 
 #endif  // IPC_IPC_MESSAGE_H_