Let prefetched resources skip cache revalidation once for a short duration.

net/http/http_transaction_test_util.h

 // Copyright 2014 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 NET_HTTP_HTTP_TRANSACTION_UNITTEST_H_
 #define NET_HTTP_HTTP_TRANSACTION_UNITTEST_H_
 
 #include "net/http/http_transaction.h"
 
 #include <string>
@@ skipping 273 matching lines @@
   void ClearLastTransaction() {
     last_transaction_.reset();
   }
 
   // net::HttpTransactionFactory:
   int CreateTransaction(net::RequestPriority priority,
                         scoped_ptr<net::HttpTransaction>* trans) override;
   net::HttpCache* GetCache() override;
   net::HttpNetworkSession* GetSession() override;
 
+  // The caller must guarantee that |clock| will outlive this object.
+  void set_clock(base::Clock* clock) {
+    DCHECK(!clock_);

[rvargas (doing something else), 2015/01/09 02:25:34]

Logging doesn't qualify anymore as trivial accessor. (and it's a good practice
to avoid logging from header files)

[jkarlin, 2015/01/09 14:03:51]

Done.

+    clock_ = clock;
+  }
+  base::Clock* clock() const { return clock_; }
+
+  // The current time (will use clock_ if it is non NULL).
+  base::Time Now();
+
  private:
   int transaction_count_;
   bool done_reading_called_;
   bool stop_caching_called_;
   net::RequestPriority last_create_transaction_priority_;
+
+  // By default clock_ is NULL but it can be set to a custom clock by test
+  // frameworks using set_clock.
+  base::Clock* clock_;
+
   base::WeakPtr<MockNetworkTransaction> last_transaction_;
 };
 
 //-----------------------------------------------------------------------------
 // helpers
 
 // read the transaction completely
 int ReadTransaction(net::HttpTransaction* trans, std::string* result);
 
 #endif  // NET_HTTP_HTTP_TRANSACTION_UNITTEST_H_