AU: Push seeks in http fetching to the progress percentage.

mock_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_MOCK_HTTP_FETCHER_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_MOCK_HTTP_FETCHER_H__
 
 #include <vector>
 #include <glib.h>
 #include "base/logging.h"
@@ skipping 17 matching lines @@
   // the transfer begins.
   MockHttpFetcher(const char* data, size_t size)
       : sent_size_(0), timeout_source_(NULL), timout_tag_(0), paused_(false) {
     data_.insert(data_.end(), data, data + size);
   }
 
   // Cleans up all internal state. Does not notify delegate
   ~MockHttpFetcher();
 
   // Ignores this.
-  virtual void SetOffset(off_t offset) {}
+  virtual void SetOffset(off_t offset) {
+    sent_size_ = offset;
+    if (delegate_)
+      delegate_->SeekToOffset(offset);
+  }
 
   // Begins the transfer if it hasn't already begun.
   virtual void BeginTransfer(const std::string& url);
 
   // If the transfer is in progress, aborts the transfer early.
   // The transfer cannot be resumed.
   virtual void TerminateTransfer();
 
   // Suspend the mock transfer.
   virtual void Pause();
@@ skipping 38 matching lines @@
 
   // True iff the fetcher is paused.
   bool paused_;
 
   DISALLOW_COPY_AND_ASSIGN(MockHttpFetcher);
 };
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_MOCK_HTTP_FETCHER_H__