Add window manager component.

wm/host/foreign_window_host_delegate.h

Index: wm/host/foreign_window_host_delegate.h
diff --git a/wm/host/foreign_window_host_delegate.h b/wm/host/foreign_window_host_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..bf9436e13e434bc6e34e9b09a7cdd63a916fb7c1
--- /dev/null
+++ b/wm/host/foreign_window_host_delegate.h
@@ -0,0 +1,22 @@
+// Copyright (c) 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 WM_HOST_FOREIGN_WINDOW_HOST_DELEGATE_H_
+#define WM_HOST_FOREIGN_WINDOW_HOST_DELEGATE_H_
+
+namespace wm {
+
+// A private interface used by ForeignWindowHost implementations to communicate
+// with their owning ForeignWindow.
+class ForeignWindowHostDelegate {
+ public:
+  virtual void OnWindowContentsChanged() = 0;
+
+ protected:
+  virtual ~ForeignWindowHostDelegate() {}
+};
+
+}  // namespace wm
+
+#endif  // WM_HOST_FOREIGN_WINDOW_HOST_DELEGATE_H_