Change UMA OfflinePages.PageSize to have better resolution in a typical range of offline page sizes.

components/offline_pages/offline_page_model.cc

 // Copyright 2015 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 "components/offline_pages/offline_page_model.h"
 
 #include <algorithm>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 553 matching lines @@
                                             const OfflinePageItem& offline_page,
                                             bool success) {
   SavePageResult result;
   if (success) {
     offline_pages_[offline_page.offline_id] = offline_page;
     result = SavePageResult::SUCCESS;
     UMA_HISTOGRAM_TIMES(
         AddHistogramSuffix(
             offline_page.client_id, "OfflinePages.SavePageTime").c_str(),
         base::Time::Now() - offline_page.creation_time);
-    UMA_HISTOGRAM_MEMORY_KB(
-        AddHistogramSuffix(
-            offline_page.client_id, "OfflinePages.PageSize").c_str(),
+    // 50 buckets capped between 1Kb and 10Mb.
+    UMA_HISTOGRAM_COUNTS_10000(AddHistogramSuffix(
+        offline_page.client_id, "OfflinePages.PageSize").c_str(),
         offline_page.file_size / 1024);
   } else {
     result = SavePageResult::STORE_FAILURE;
   }
   InformSavePageDone(callback, result, offline_page.client_id,
                      offline_page.offline_id);
   DeletePendingArchiver(archiver);
 
   FOR_EACH_OBSERVER(Observer, observers_, OfflinePageModelChanged(this));
 }
@@ skipping 239 matching lines @@
 void OfflinePageModel::RunWhenLoaded(const base::Closure& task) {
   if (!is_loaded_) {
     delayed_tasks_.push_back(task);
     return;
   }
 
   base::ThreadTaskRunnerHandle::Get()->PostTask(FROM_HERE, task);
 }
 
 }  // namespace offline_pages