Add exports needed for glue to build as a component.

webkit/extensions/v8/playback_extension.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 WEBKIT_EXTENSIONS_V8_PLAYBACK_EXTENSION_H_
 #define WEBKIT_EXTENSIONS_V8_PLAYBACK_EXTENSION_H_
 #pragma once
 
+#include "webkit/extensions/webkit_extensions_export.h"
+
 namespace v8 {
 class Extension;
 }
 
 namespace extensions_v8 {
 
 // Inject code which overrides a few common JS functions for implementing
 // randomness.  In order to implement effective record & playback of
 // websites, it is important that the URLs not change.  Many popular web
 // based apps use randomness in URLs to unique-ify urls for proxies.
 // Unfortunately, this breaks playback.
 // To work around this, we take the two most common client-side randomness
 // generators and make them constant.  They really need to be constant
 // (rather than a constant seed followed by constant change)
 // because the playback mode wants flexibility in how it plays them back
 // and cannot always guarantee that requests for randomness are played back
 // in exactly the same order in which they were recorded.
 class PlaybackExtension {
  public:
-  static v8::Extension* Get();
+  WEBKIT_EXTENSIONS_EXPORT static v8::Extension* Get();
 };
 
 }  // namespace extensions_v8
 
 #endif  // WEBKIT_EXTENSIONS_V8_PLAYBACK_EXTENSION_H_