Refactor GuestViewContainer to split out WebView related logic and MimeHandlerView related logic.

extensions/renderer/guest_view/mime_handler_view_container.h

+// 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 EXTENSIONS_RENDERER_GUEST_VIEW_MIME_HANDLER_VIEW_CONTAINER_H_
+#define EXTENSIONS_RENDERER_GUEST_VIEW_MIME_HANDLER_VIEW_CONTAINER_H_
+
+#include "extensions/renderer/guest_view/guest_view_container.h"
+
+namespace extensions {
+
+class MimeHandlerViewContainer : public GuestViewContainer {
+ public:
+  MimeHandlerViewContainer(content::RenderFrame* render_frame,
+                           const std::string& mime_type);
+  ~MimeHandlerViewContainer() override;
+
+  // BrowserPluginDelegate implementation.
+  void DidFinishLoading() override;
+  void DidReceiveData(const char* data, int data_length) override;
+
+  // GuestViewContainer override.
+  bool HandlesMessage(const IPC::Message& message) override;
+  bool OnMessage(const IPC::Message& message) override;
+
+ private:
+  void OnCreateMimeHandlerViewGuestACK(int element_instance_id);
+
+  const std::string mime_type_;
+  std::string html_string_;
+
+  DISALLOW_COPY_AND_ASSIGN(MimeHandlerViewContainer);
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_RENDERER_GUEST_VIEW_MIME_HANDLER_VIEW_CONTAINER_H_