AU: Fix potential issues with premature destruction of HTTP fetchers.

mock_http_fetcher.cc

 // 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.
 
 #include "update_engine/mock_http_fetcher.h"
 #include <algorithm>
 #include "base/logging.h"
 
 // This is a mac implementation of HttpFetcher which is useful for testing.
 
@@ skipping 23 matching lines @@
     SignalTransferComplete();
     return timeout_source_;
   }
 
   CHECK_LT(sent_size_, data_.size());
   if (!skip_delivery) {
     const size_t chunk_size = min(kMockHttpFetcherChunkSize,
                                   data_.size() - sent_size_);
     CHECK(delegate_);
     delegate_->ReceivedBytes(this, &data_[sent_size_], chunk_size);
+    // We may get terminated in the callback.
+    if (sent_size_ == data_.size()) {
+      LOG(INFO) << "Terminated in the ReceivedBytes callback.";
+      return timeout_source_;
+    }
     sent_size_ += chunk_size;
     CHECK_LE(sent_size_, data_.size());
     if (sent_size_ == data_.size()) {
       // We've sent all the data. Notify of success.
       SignalTransferComplete();
     }
   }
 
   if (paused_) {
     // If we're paused, we should return true if timeout_source_ is set,
@@ skipping 20 matching lines @@
   bool ret = SendData(false);
   if (false == ret) {
     timeout_source_ = NULL;
   }
   return ret;
 }
 
 // If the transfer is in progress, aborts the transfer early.
 // The transfer cannot be resumed.
 void MockHttpFetcher::TerminateTransfer() {
+  LOG(INFO) << "Terminating transfer.";
   sent_size_ = data_.size();
   // kill any timeout
   if (timeout_source_) {
     g_source_remove(timout_tag_);
     g_source_destroy(timeout_source_);
     timeout_source_ = NULL;
   }
+  delegate_->TransferTerminated(this);
 }
 
 void MockHttpFetcher::Pause() {
   CHECK(!paused_);
   paused_ = true;
   if (timeout_source_) {
     g_source_remove(timout_tag_);
     g_source_destroy(timeout_source_);
     timeout_source_ = NULL;
   }
@@ skipping 16 matching lines @@
 void MockHttpFetcher::SignalTransferComplete() {
   // If the transfer has been failed, the HTTP response code should be set
   // already.
   if (!fail_transfer_) {
     http_response_code_ = 200;
   }
   delegate_->TransferComplete(this, !fail_transfer_);
 }
 
 }  // namespace chromeos_update_engine