Support embedded plugins with MimeHandlerView.

extensions/renderer/guest_view/mime_handler_view_container.h

Index: extensions/renderer/guest_view/mime_handler_view_container.h
diff --git a/extensions/renderer/guest_view/mime_handler_view_container.h b/extensions/renderer/guest_view/mime_handler_view_container.h
index 72c93470be00e3737b87720dcf95f2a562e29d98..5fcf51637814afd5ada14b88d104c5dbbcd331e7 100644
--- a/extensions/renderer/guest_view/mime_handler_view_container.h
+++ b/extensions/renderer/guest_view/mime_handler_view_container.h
@@ -6,29 +6,76 @@
 #define EXTENSIONS_RENDERER_GUEST_VIEW_MIME_HANDLER_VIEW_CONTAINER_H_
 
 #include "extensions/renderer/guest_view/guest_view_container.h"
+#include "third_party/WebKit/public/platform/WebURLLoader.h"
+#include "third_party/WebKit/public/platform/WebURLLoaderClient.h"
+#include "url/gurl.h"
 
 namespace extensions {
 
-class MimeHandlerViewContainer : public GuestViewContainer {
+// A container for loading up an extension inside a BrowserPlugin to handle a
+// MIME type. A request for the URL of the data to load inside the container is
+// made and a url is sent back in response which points to the URL which the
+// container should be navigated to. There are two cases for making this URL
+// request, the case where the plugin is embedded and the case where it is top
+// level:
+// 1) In the top level case a URL request for the data to load has already been
+//    made by the renderer on behalf of the plugin. The |DidReceiveData| and
+//    |DidFinishLoading| callbacks (from BrowserPluginDelegate) will be called
+//    when data is received and when it has finished being received,
+//    respectively.
+// 2) In the embedded case, no URL request is automatically made by the
+//    renderer. We make a URL request for the data inside the container using
+//    a WebURLLoader. In this case, the |didReceiveData| and |didFinishLoading|
+//    (from WebURLLoaderClient) when data is received and when it has finished
+//    being received.
+class MimeHandlerViewContainer : public GuestViewContainer,
+                                 public blink::WebURLLoaderClient {
  public:
   MimeHandlerViewContainer(content::RenderFrame* render_frame,
-                           const std::string& mime_type);
+                           const std::string& mime_type,
+                           const GURL& original_url);
   ~MimeHandlerViewContainer() override;
 
   // BrowserPluginDelegate implementation.
   void DidFinishLoading() override;
   void DidReceiveData(const char* data, int data_length) override;
+  void Ready() override;
 
-  // GuestViewContainer override.
+  // GuestViewContainer overrides.
   bool HandlesMessage(const IPC::Message& message) override;
   bool OnMessage(const IPC::Message& message) override;
 
+  // WebURLLoaderClient overrides.
+  void didReceiveData(blink::WebURLLoader* loader,
+                      const char* data,
+                      int data_length,
+                      int encoded_data_length) override;
+  void didFinishLoading(blink::WebURLLoader* loader,
+                        double finish_time,
+                        int64_t total_encoded_data_length) override;
+
  private:
+  // Message handlers.
   void OnCreateMimeHandlerViewGuestACK(int element_instance_id);
 
+  void CreateMimeHandlerViewGuest();
+
+  // The MIME type of the plugin.
   const std::string mime_type_;
+
+  // The URL of the extension to navigate to.
   std::string html_string_;
 
+  // Whether the plugin is embedded or not.
+  bool is_embedded_;
+
+  // The original URL of the plugin.
+  GURL original_url_;
+
+  // A URL loader to load the |original_url_| when the plugin is embedded. In
+  // the embedded case, no URL request is made automatically.
+  scoped_ptr<blink::WebURLLoader> loader_;
+
   DISALLOW_COPY_AND_ASSIGN(MimeHandlerViewContainer);
 };