[gin] Turn gin into a component

gin/gin_export.h

Index: gin/gin_export.h
diff --git a/gin/gin_export.h b/gin/gin_export.h
new file mode 100644
index 0000000000000000000000000000000000000000..fc4bf9bc00305cc8f02ec3a8b3598c1b4642087b
--- /dev/null
+++ b/gin/gin_export.h
@@ -0,0 +1,29 @@
+// Copyright 2013 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 GIN_GIN_EXPORT_H_
+#define GIN_GIN_EXPORT_H_
+
+#if defined(COMPONENT_BUILD)
+#if defined(WIN32)
+
+#if defined(GIN_IMPLEMENTATION)
+#define GIN_EXPORT __declspec(dllexport)
+#else
+#define GIN_EXPORT __declspec(dllimport)
+#endif  // defined(GIN_IMPLEMENTATION)
+
+#else  // defined(WIN32)
+#if defined(GIN_IMPLEMENTATION)
+#define GIN_EXPORT __attribute__((visibility("default")))
+#else
+#define GIN_EXPORT
+#endif  // defined(GIN_IMPLEMENTATION)
+#endif
+
+#else  // defined(COMPONENT_BUILD)
+#define GIN_EXPORT
+#endif
+
+#endif  // GIN_GIN_EXPORT_H_