Move most of ChromeV8Context to a base ScriptContext

chrome/renderer/extensions/request_sender.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 CHROME_RENDERER_EXTENSIONS_REQUEST_SENDER_H_
-#define CHROME_RENDERER_EXTENSIONS_REQUEST_SENDER_H_
-
-#include <string>
-#include <map>
-
-#include "base/memory/linked_ptr.h"
-#include "v8/include/v8.h"
-
-namespace base {
-class ListValue;
-}
-
-namespace extensions {
-class ChromeV8Context;
-class Dispatcher;
-
-struct PendingRequest;
-
-// Responsible for sending requests for named extension API functions to the
-// extension host and routing the responses back to the caller.
-class RequestSender {
- public:
-  // Source represents a user of RequestSender. Every request is associated with
-  // a Source object, which will be notified when the corresponding response
-  // arrives. When a Source object is going away and there are pending requests,
-  // it should call InvalidateSource() to make sure no notifications are sent to
-  // it later.
-  class Source {
-   public:
-    virtual ~Source() {}
-
-    virtual ChromeV8Context* GetContext() = 0;
-    virtual void OnResponseReceived(const std::string& name,
-                                    int request_id,
-                                    bool success,
-                                    const base::ListValue& response,
-                                    const std::string& error) = 0;
-  };
-
-  // Helper class to (re)set the |source_tab_id_| below.
-  class ScopedTabID {
-   public:
-    ScopedTabID(RequestSender* request_sender, int tab_id);
-    ~ScopedTabID();
-
-   private:
-    RequestSender* const request_sender_;
-    const int tab_id_;
-    const int previous_tab_id_;
-
-    DISALLOW_COPY_AND_ASSIGN(ScopedTabID);
-  };
-
-  explicit RequestSender(Dispatcher* dispatcher);
-  ~RequestSender();
-
-  // In order to avoid collision, all |request_id|s passed into StartRequest()
-  // should be generated by this method.
-  int GetNextRequestId() const;
-
-  // Makes a call to the API function |name| that is to be handled by the
-  // extension host. The response to this request will be received in
-  // HandleResponse().
-  // TODO(koz): Remove |request_id| and generate that internally.
-  //            There are multiple of these per render view though, so we'll
-  //            need to vend the IDs centrally.
-  void StartRequest(Source* source,
-                    const std::string& name,
-                    int request_id,
-                    bool has_callback,
-                    bool for_io_thread,
-                    base::ListValue* value_args);
-
-  // Handles responses from the extension host to calls made by StartRequest().
-  void HandleResponse(int request_id,
-                      bool success,
-                      const base::ListValue& response,
-                      const std::string& error);
-
-  // Notifies this that a request source is no longer valid.
-  // TODO(kalman): Do this in a generic/safe way.
-  void InvalidateSource(Source* source);
-
- private:
-  friend class ScopedTabID;
-  typedef std::map<int, linked_ptr<PendingRequest> > PendingRequestMap;
-
-  void InsertRequest(int request_id, PendingRequest* pending_request);
-  linked_ptr<PendingRequest> RemoveRequest(int request_id);
-
-  Dispatcher* dispatcher_;
-  PendingRequestMap pending_requests_;
-
-  int source_tab_id_;  // Id of the tab sending the request, or -1 if no tab.
-
-  DISALLOW_COPY_AND_ASSIGN(RequestSender);
-};
-
-}  // namespace extensions
-
-#endif  // CHROME_RENDERER_EXTENSIONS_REQUEST_SENDER_H_