Introduce a delegate to avoid hardcoding "chrome-extension" in net/.

net/url_request/url_request_throttler_entry_interface.h

 // Copyright (c) 2011 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 NET_URL_REQUEST_URL_REQUEST_THROTTLER_ENTRY_INTERFACE_H_
 #define NET_URL_REQUEST_URL_REQUEST_THROTTLER_ENTRY_INTERFACE_H_
 #pragma once
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/time.h"
 #include "net/base/net_export.h"
 
 namespace net {
 
+class URLRequest;
 class URLRequestThrottlerHeaderInterface;
 
 // Interface provided on entries of the URL request throttler manager.
 class NET_EXPORT URLRequestThrottlerEntryInterface
     : public base::RefCountedThreadSafe<URLRequestThrottlerEntryInterface> {
  public:
   URLRequestThrottlerEntryInterface() {}
 
   // Returns true when we have encountered server errors and are doing
-  // exponential back-off, unless the request has |load_flags| (from
-  // net/base/load_flags.h) that mean it is likely to be
-  // user-initiated.
+  // exponential back-off, unless the request has load flags that mean
+  // it is likely to be user-initiated, or the NetworkDelegate returns
+  // false for |CanThrottleRequest(request)|.
   //
   // URLRequestHttpJob checks this method prior to every request; it
   // cancels requests if this method returns true.
-  virtual bool ShouldRejectRequest(int load_flags) const = 0;
+  virtual bool ShouldRejectRequest(const URLRequest& request) const = 0;
 
   // Calculates a recommended sending time for the next request and reserves it.
   // The sending time is not earlier than the current exponential back-off
   // release time or |earliest_time|. Moreover, the previous results of
   // the method are taken into account, in order to make sure they are spread
   // properly over time.
   // Returns the recommended delay before sending the next request, in
   // milliseconds. The return value is always positive or 0.
   // Although it is not mandatory, respecting the value returned by this method
   // is helpful to avoid traffic overload.
@@ skipping 20 matching lines @@
   virtual ~URLRequestThrottlerEntryInterface() {}
 
  private:
   friend class base::RefCounted<URLRequestThrottlerEntryInterface>;
   DISALLOW_COPY_AND_ASSIGN(URLRequestThrottlerEntryInterface);
 };
 
 }  // namespace net
 
 #endif  // NET_URL_REQUEST_URL_REQUEST_THROTTLER_ENTRY_INTERFACE_H_