Forward MIME types to BrowserPlugin when a viewer is specified.

content/public/browser/resource_dispatcher_host_delegate.h

 // Copyright (c) 2012 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 CONTENT_PUBLIC_BROWSER_RESOURCE_DISPATCHER_HOST_DELEGATE_H_
 #define CONTENT_PUBLIC_BROWSER_RESOURCE_DISPATCHER_HOST_DELEGATE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 83 matching lines @@
   // Returns true if we should force the given resource to be downloaded.
   // Otherwise, the content layer decides.
   virtual bool ShouldForceDownloadResource(
       const GURL& url, const std::string& mime_type);
 
   // Returns true and sets |origin| and |target_id| if a Stream should be
   // created for the resource.
   // If true is returned, a new Stream will be created and OnStreamCreated()
   // will be called with
   // - the |target_id| returned by this function
+  // - If the stream will be rendered in a BrowserPlugin, |view_id| will
+  //   contain a GUID that can be used to uniquely identify it.
   // - a StreamHandle instance for the Stream. The handle contains the URL for
   //   reading the Stream etc.
   // The Stream's origin will be set to |origin|.
+  //
+  // If the stream will be rendered in a BrowserPlugin, |payload| will contain
+  // the data that should be given to the old ResourceHandler to forward to the
+  // renderer process.
   virtual bool ShouldInterceptResourceAsStream(
       content::ResourceContext* resource_context,
       const GURL& url,
       const std::string& mime_type,
       GURL* origin,
-      std::string* target_id);
+      std::string* target_id,
+      std::string* payload,
+      std::string* view_id);

[jam, 2014/05/30 23:04:16]

if my reading is correct, content calls chrome with this method to get a
"view_id", and then it calls it back right after with the view_id that chrome
gave it.

why can't chrome cache this itself in its delegate implementation, based on a
key that is based on the existing parameters?

[Zachary Kuznia, 2014/05/30 23:40:55]

None of the other parameters are guaranteed to be unique.  The target_id could
possibly be used for this purpose, but it will be removed once all the clients
have migrated to the new API.

[jam, 2014/06/02 06:41:53]

I see. Ok, since I'd really like to avoid this extra concept in the public API
as it's chrome-specific, let's make this method and the one below have a first
parameter as the net::URLRequest* to match most of the methods in this
interface. the chrome delegate can then keep its own mapping from
child_id+request_id to target_id+view_id. this method can then drop the
resource_context/url, while the next method can drop all the parameters other
than the StreamHandle since they're accessible from the net::URLRequest

[Zachary Kuznia, 2014/06/05 22:28:22]

Done.

 
   // Informs the delegate that a Stream was created. |target_id| will be filled
   // with the parameter returned by ShouldInterceptResourceAsStream(). The
   // Stream can be read from the blob URL of the Stream, but can only be read
   // once.
   virtual void OnStreamCreated(
       content::ResourceContext* resource_context,
       int render_process_id,
       int render_view_id,
       const std::string& target_id,
+      const std::string& view_id,
       scoped_ptr<StreamHandle> stream,
       int64 expected_content_size);
 
   // Informs the delegate that a response has started.
   virtual void OnResponseStarted(
       net::URLRequest* request,
       ResourceContext* resource_context,
       ResourceResponse* response,
       IPC::Sender* sender);
 
   // Informs the delegate that a request has been redirected.
   virtual void OnRequestRedirected(
       const GURL& redirect_url,
       net::URLRequest* request,
       ResourceContext* resource_context,
       ResourceResponse* response);
 
   // Notification that a request has completed.
   virtual void RequestComplete(net::URLRequest* url_request);
 
  protected:
   ResourceDispatcherHostDelegate();
   virtual ~ResourceDispatcherHostDelegate();
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_RESOURCE_DISPATCHER_HOST_DELEGATE_H_