Pass pepper apps API calls through the existing js apps API bindings.

chrome/renderer/extensions/pepper_request_proxy.h

+// Copyright 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 CHROME_RENDERER_EXTENSIONS_PEPPER_REQUEST_PROXY_H_
+#define CHROME_RENDERER_EXTENSIONS_PEPPER_REQUEST_PROXY_H_
+
+#include <map>
+#include <string>
+
+namespace base {
+class ListValue;
+}
+
+namespace extensions {
+
+class ChromeV8Context;
+
+// A proxy that forwards pepper apps API calls through the Javascript API
+// bindings.
+class PepperRequestProxy {
+ public:
+  class Source {
+   public:
+    virtual ~Source() {}
+
+    // Called with the result of an API call. If |success| is true, |response|
+    // will contain the response value. Otherwise, |error| will contain the
+    // error message.
+    virtual void OnResponseReceived(int request_id,
+                                    bool success,
+                                    const base::ListValue& response,
+                                    const std::string& error) = 0;
+  };
+
+  explicit PepperRequestProxy(ChromeV8Context* context);
+  ~PepperRequestProxy();
+
+  // Starts an API request. Returns whether the call was successful. If the call
+  // was successful, |request_id| will contain the request ID that will be
+  // passed to the OnResponseReceived method of |source| when the response is
+  // received. Otherwise, |error| will contain the error message.
+  // OnResponseReceived will only be called if |has_callback| is true.

[yzshen1, 2013/11/26 19:33:11]

Will it be called if |has_callback| is true but the method failed? (I guess not
but better to be explicit.)

[Sam McNally, 2013/11/27 23:40:26]

Done.

+  bool StartRequest(Source* source,

[yzshen1, 2013/11/26 19:33:11]

Is it better to use a base::Callback instead of |source|?

[Sam McNally, 2013/11/27 23:40:26]

Done.

+                    const std::string& request_name,
+                    bool has_callback,
+                    base::ListValue& args,
+                    int* request_id,
+                    std::string* error);
+
+  void OnResponse(int request_id,

[yzshen1, 2013/11/26 19:33:11]

nit: OnResponseReceived might sound better.

[Sam McNally, 2013/11/27 23:40:26]

Done.

+                  bool success,
+                  const base::ListValue& args,
+                  const std::string& error);
+
+  // Invalidates all API calls in-flight for a source. This should be called
+  // when a Source is destroyed.
+  void InvalidateSource(Source* source);
+
+ private:
+  typedef std::map<int, Source*> PendingRequestMap;
+  ChromeV8Context* context_;

[yzshen1, 2013/11/26 19:33:11]

Please comment about the ownership/lifespan of context_.

[Sam McNally, 2013/11/27 23:40:26]

Done.

+  PendingRequestMap pending_request_map_;
+  int next_request_id_;
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_RENDERER_EXTENSIONS_PEPPER_REQUEST_PROXY_H_