Use InterstitialPage through a delegate interface instead of deriving from it.

chrome/browser/chromeos/offline/offline_load_page_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 "chrome/browser/chromeos/cros/cros_library.h"
 #include "chrome/browser/chromeos/offline/offline_load_page.h"
 #include "chrome/test/base/chrome_render_view_host_test_harness.h"
+#include "content/browser/tab_contents/interstitial_page.h"
 #include "content/browser/tab_contents/test_tab_contents.h"
 #include "content/test/test_browser_thread.h"
 
 using content::BrowserThread;
 
 static const char* kURL1 = "http://www.google.com/";
 static const char* kURL2 = "http://www.gmail.com/";
 
 namespace chromeos {
 
@@ skipping 53 matching lines @@
       user_response_ = CANCEL;
   }
 
   void Navigate(const char* url, int page_id) {
     contents()->TestDidNavigate(
         contents()->GetRenderViewHost(), page_id, GURL(url),
         content::PAGE_TRANSITION_TYPED);
   }
 
   void ShowInterstitial(const char* url) {
-    (new TestOfflineLoadPage(contents(), GURL(url), this))->Show();
+    new TestOfflineLoadPage(contents(), GURL(url), this);
   }
 
   // Returns the OfflineLoadPage currently showing or NULL if none is
   // showing.
   InterstitialPage* GetOfflineLoadPage() {
     return InterstitialPage::GetInterstitialPage(contents());
   }
 
   UserResponse user_response() const { return user_response_; }
 
@@ skipping 60 matching lines @@
   // The interstitial should be gone.
   EXPECT_EQ(CANCEL, user_response());
   EXPECT_FALSE(GetOfflineLoadPage());
   // We did not proceed, the pending entry should be gone.
   EXPECT_FALSE(controller().GetPendingEntry());
   // the URL is set back to kURL1.
   EXPECT_EQ(kURL1, contents()->GetURL().spec());
 }
 
 }  // namespace chromeos