Add histograms for network activity, and total/cumulative

net/http/http_cache_unittest.cc

 // Copyright (c) 2012 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.
 
 #include "net/http/http_cache.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/memory/scoped_vector.h"
 #include "base/message_loop.h"
@@ skipping 62 matching lines @@
   virtual void OnCacheActionStart() {
     EXPECT_FALSE(action_in_progress_);
     EXPECT_GT(num_remaining_actions_to_observe_, 0);
     num_remaining_actions_to_observe_--;
     action_in_progress_ = true;
   }
   virtual void OnCacheActionFinish() {
     EXPECT_TRUE(action_in_progress_);
     action_in_progress_ = false;
   }
+  virtual void OnNetworkActionStart() {}
+  virtual void OnNetworkActionFinish() {}
 
  private:
   int num_remaining_actions_to_observe_;
   bool action_in_progress_;
 };
 
 void ReadAndVerifyTransaction(net::HttpTransaction* trans,
                               const MockTransaction& trans_info) {
   std::string content;
   int rv = ReadTransaction(trans, &content);
@@ skipping 4933 matching lines @@
                                  8);
 
   // Force this transaction to read from the cache.
   MockTransaction transaction(kSimpleGET_Transaction);
   transaction.load_flags |= net::LOAD_ONLY_FROM_CACHE;
 
   RunTransactionTestWithDelegate(cache.http_cache(),
                                  kSimpleGET_Transaction,
                                  5);
 }