AU: MultiHttpFetcher cleanup/rewrite

http_fetcher.h

 // Copyright (c) 2009 The Chromium OS 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 CHROMEOS_PLATFORM_UPDATE_ENGINE_HTTP_FETCHER_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_HTTP_FETCHER_H__
 
 #include <deque>
 #include <string>
 #include <vector>
@@ skipping 68 matching lines @@
   // Used to unpause an HttpFetcher and let the bytes stream in again.
   // If a delegate is set, ReceivedBytes() may be called on it before
   // Unpause() returns
   virtual void Unpause() = 0;
 
   // These two function are overloaded in LibcurlHttp fetcher to speed
   // testing.
   virtual void set_idle_seconds(int seconds) {}
   virtual void set_retry_seconds(int seconds) {}
 
+  ProxyResolver* proxy_resolver() const { return proxy_resolver_; }
+
+  // These are used for testing:
+  virtual void SetConnectionAsExpensive(bool is_expensive) {}
+  virtual void SetBuildType(bool is_official) {}
+
  protected:
   // The URL we're actively fetching from
   std::string url_;
 
   // POST data for the transfer, and whether or not it was ever set
   bool post_data_set_;
   std::vector<char> post_data_;
 
   // The server's HTTP response code from the last transfer. This
   // field should be set to 0 when a new transfer is initiated, and
@@ skipping 16 matching lines @@
 class HttpFetcherDelegate {
  public:
   // Called every time bytes are received.
   virtual void ReceivedBytes(HttpFetcher* fetcher,
                              const char* bytes,
                              int length) = 0;
 
   // Called if the fetcher seeks to a particular offset.
   virtual void SeekToOffset(off_t offset) {}
 
-  // Called when the transfer has completed successfully or been aborted through
-  // means other than TerminateTransfer. It's OK to destroy the |fetcher| object
-  // in this callback.
+  // When a transfer has completed, exactly one of these two methods will be
+  // called. TransferTerminated is called when the transfer has been aborted
+  // through TerminateTransfer. TransferComplete is called in all other
+  // situations. It's OK to destroy the |fetcher| object in this callback.
   virtual void TransferComplete(HttpFetcher* fetcher, bool successful) = 0;
-
-  // Called when the transfer has been aborted through TerminateTransfer. It's
-  // OK to destroy the |fetcher| object in this callback.
   virtual void TransferTerminated(HttpFetcher* fetcher) {}
 };
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_HTTP_FETCHER_H__