--- chrome/common/plugin_messages_internal.h
+++ chrome/common/plugin_messages_internal.h
@@ -113,7 +113,7 @@ IPC_BEGIN_MESSAGES(PluginProcessHost)
                       HWND /* caller window */)
 #endif
 
-#if defined(OS_LINUX)
+#if defined(USE_X11)
   // On Linux, the mapping between NativeViewId and X window ids
   // is known only to the browser.  This message lets the plugin process
   // ask about a NativeViewId that was provided by the renderer.
diff --git chrome/common/pref_names.cc chrome/common/pref_names.cc
index f417d63..70737be 100644