Rewrite scoped_ptr<T>(NULL) to use the default ctor in chrome/.

chrome/browser/prerender/prerender_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 "base/command_line.h"
 #include "base/format_macros.h"
 #include "base/memory/scoped_vector.h"
 #include "base/message_loop.h"
 #include "base/strings/stringprintf.h"
 #include "base/time.h"
@@ skipping 76 matching lines @@
 class UnitTestPrerenderManager : public PrerenderManager {
  public:
   using PrerenderManager::kMinTimeBetweenPrerendersMs;
   using PrerenderManager::kNavigationRecordWindowMs;
 
   explicit UnitTestPrerenderManager(Profile* profile,
                                     PrerenderTracker* prerender_tracker)
       : PrerenderManager(profile, prerender_tracker),
         time_(Time::Now()),
         time_ticks_(TimeTicks::Now()),
-        next_prerender_contents_(NULL),
         prerender_tracker_(prerender_tracker) {
     set_rate_limit_enabled(false);
   }
 
   virtual ~UnitTestPrerenderManager() {
   }
 
   // From BrowserContextKeyedService, via PrererenderManager:
   virtual void Shutdown() OVERRIDE {
     if (next_prerender_contents())
@@ skipping 1307 matching lines @@
   EXPECT_EQ(null, prerender_manager()->FindEntry(second_url));
 
   // The first prerender should have died, giving life to the second one.
   prerender_manager()->AdvanceTimeTicks(wait_for_first_prerender_to_expire);
   EXPECT_EQ(null, prerender_manager()->FindEntry(first_url));
   EXPECT_EQ(second_prerender_contents,
             prerender_manager()->FindAndUseEntry(second_url));
 }
 
 }  // namespace prerender