[Offline Pages] Add cached offline page utils and show usage in settings.

chrome/browser/browsing_data/conditional_cache_counting_helper_browsertest.cc

 // Copyright (c) 2016 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 <algorithm>
 #include <memory>
 #include <set>
 #include <string>
 
 #include "base/run_loop.h"
@@ skipping 17 matching lines @@
         base::Bind(&ConditionalCacheCountingHelperBrowserTest::CountCallback,
                    base::Unretained(this));
 
     cache_util_ = base::MakeUnique<content::CacheTestUtil>(
         content::BrowserContext::GetDefaultStoragePartition(
             browser()->profile()));
   }
 
   void TearDownOnMainThread() override { cache_util_.reset(); }
 
-  void CountCallback(int64_t size, bool is_upper_limit) {
+  void CountCallback(bool is_upper_limit, int64_t size) {
     // Negative values represent an unexpected error.
     DCHECK(size >= 0 || size == net::ERR_ABORTED);
     DCHECK_CURRENTLY_ON(BrowserThread::UI);
     last_size_ = size;
     last_is_upper_limit_ = is_upper_limit;
 
     if (run_loop_)
       run_loop_->Quit();
   }
 
@@ skipping 74 matching lines @@
     EXPECT_EQ(size_1_2, size_1_3);
     EXPECT_EQ(size_2_3, size_1_3);
   } else {
     EXPECT_GT(size_1_2, 0);
     EXPECT_GT(size_2_3, 0);
     EXPECT_LT(size_1_2, size_1_3);
     EXPECT_LT(size_2_3, size_1_3);
     EXPECT_EQ(size_1_2 + size_2_3, size_1_3);
   }
 }