Add delegate to install web_contents helpers for MimeHandlerView.

chrome/browser/guest_view/mime_handler_view/chrome_mime_handler_view_guest_delegate.h

Index: chrome/browser/guest_view/mime_handler_view/chrome_mime_handler_view_guest_delegate.h
diff --git a/chrome/browser/guest_view/mime_handler_view/chrome_mime_handler_view_guest_delegate.h b/chrome/browser/guest_view/mime_handler_view/chrome_mime_handler_view_guest_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..4e94e41f2ac62fd297a1d34737aeaed5d577e28a
--- /dev/null
+++ b/chrome/browser/guest_view/mime_handler_view/chrome_mime_handler_view_guest_delegate.h
@@ -0,0 +1,29 @@
+// Copyright 2014 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 CHROME_BROWSER_GUEST_VIEW_MIME_HANDLER_VIEW_CHROME_MIME_HANDLER_VIEW_GUEST_DELEGATE_H_
+#define CHROME_BROWSER_GUEST_VIEW_MIME_HANDLER_VIEW_CHROME_MIME_HANDLER_VIEW_GUEST_DELEGATE_H_
+
+#include "extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest_delegate.h"
+
+namespace content {
+class WebContents;
+}  // namespace content
+
+class ChromeMimeHandlerViewGuestDelegate
+    : public extensions::MimeHandlerViewGuestDelegate {
+ public:
+  explicit ChromeMimeHandlerViewGuestDelegate(
+      extensions::MimeHandlerViewGuest* guest);
+  virtual ~ChromeMimeHandlerViewGuestDelegate();
+
+  virtual void AttachHelpers() OVERRIDE;
+
+ private:
+  extensions::MimeHandlerViewGuest* guest_;  // Owns us.
+
+  DISALLOW_COPY_AND_ASSIGN(ChromeMimeHandlerViewGuestDelegate);
+};
+
+#endif  // CHROME_BROWSER_GUEST_VIEW_MIME_HANDLER_VIEW_CHROME_MIME_HANDLER_VIEW_GUEST_DELEGATE_H_