Adds a --deterministic-fetch flag to headless_shell

headless/public/util/url_fetcher.h

 // Copyright 2016 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 HEADLESS_PUBLIC_UTIL_URL_FETCHER_H_
 #define HEADLESS_PUBLIC_UTIL_URL_FETCHER_H_
 
 #include <stddef.h>
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "net/base/net_errors.h"
 #include "url/gurl.h"
 
 namespace net {
 class HttpRequestHeaders;
 class HttpResponseHeaders;
 }  // namespace net
 
 namespace headless {
 
 // An interface for fetching URLs. Note these are only intended to be used once.
-// TODO(alexclarke): Implement a URLFetcher that can backend onto a URLRequest
-// and hook this up in headless_shell under a flag.
 class URLFetcher {
  public:
   URLFetcher() {}
   virtual ~URLFetcher() {}
 
   // Interface for reporting the fetch result.
   class ResultListener {
    public:
     ResultListener() {}
 
@@ skipping 19 matching lines @@
 
    protected:
     virtual ~ResultListener() {}
 
    private:
     DISALLOW_COPY_AND_ASSIGN(ResultListener);
   };
 
   // Instructs the sub-class to fetch the resource.
   virtual void StartFetch(const GURL& rewritten_url,
+                          const std::string& method,
                           const net::HttpRequestHeaders& request_headers,
                           ResultListener* result_listener) = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(URLFetcher);
 };
 
 }  // namespace headless
 
 #endif  // HEADLESS_PUBLIC_UTIL_URL_FETCHER_H_