Extensions: Send the tab id to platform apps.

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>
 
@@ skipping 24 matching lines @@
     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,
+                    int source_tab_id,
                     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   // Notifies this that a request source is no longer valid.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);
 
+  int sender_tab_id() const {

[not at google - send to devlin, 2014/01/28 18:45:45]

(see comment in request_sender.cc; does this need to be exposed at all?)

+    return sender_tab_id_;
+  }
+
  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 sender_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_