Add exports needed for glue to build as a component.

webkit/extensions/webkit_extensions_export.h

Index: webkit/extensions/webkit_extensions_export.h
diff --git a/webkit/extensions/webkit_extensions_export.h b/webkit/extensions/webkit_extensions_export.h
new file mode 100644
index 0000000000000000000000000000000000000000..d48c4effc3702991ffe9b7308ee3f13a84c33291
--- /dev/null
+++ b/webkit/extensions/webkit_extensions_export.h
@@ -0,0 +1,26 @@
+// 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_WEBKIT_EXTENSIONS_EXPORT_H_
+#define WEBKIT_EXTENSIONS_WEBKIT_EXTENSIONS_EXPORT_H_
+#pragma once
+
+#if 0 // defined(COMPONENT_BUILD)
+#if defined(WIN32)
+
+#if defined(WEBKIT_EXTENSIONS_IMPLEMENTATION)
+#define WEBKIT_EXTENSIONS_EXPORT __declspec(dllexport)
+#else
+#define WEBKIT_EXTENSIONS_EXPORT __declspec(dllimport)
+#endif  // defined(WEBKIT_EXTENSIONS_IMPLEMENTATION)
+
+#else // defined(WIN32)
+#define WEBKIT_EXTENSIONS_EXPORT __attribute__((visibility("default")))
+#endif
+
+#else // defined(COMPONENT_BUILD)
+#define WEBKIT_EXTENSIONS_EXPORT
+#endif
+
+#endif  // WEBKIT_EXTENSIONS_WEBKIT_EXTENSIONS_EXPORT_H_