Issue 501916 : Add data type counts to profile deletion flow

components/history/core/browser/history_service.h

Index: components/history/core/browser/history_service.h
diff --git a/components/history/core/browser/history_service.h b/components/history/core/browser/history_service.h
index fb12f816012d3865b1ae54cb3846bf1293ee0933..dc22ca14006505947b1d0d604acbd17058538597 100644
--- a/components/history/core/browser/history_service.h
+++ b/components/history/core/browser/history_service.h
@@ -331,6 +331,17 @@ class HistoryService : public syncer::SyncableService, public KeyedService {
       const QueryFilteredURLsCallback& callback,
       base::CancelableTaskTracker* tracker);
 
+  // Statistics ----------------------------------------------------------------
+
+  // Returns the count of URLs in the url database. The argument is the count.
+  // The count is zero if query to the database failed.
+  typedef base::Callback<void(int)> CountURLsCallback;
+
+  // Returns the count of URLs in the url database.
+  base::CancelableTaskTracker::TaskId HistoryService::CountURLs(
+      const CountURLsCallback& callback,
+      base::CancelableTaskTracker* tracker);
+
   // Database management operations --------------------------------------------
 
   // Delete all the information related to a single url.
@@ -438,6 +449,9 @@ class HistoryService : public syncer::SyncableService, public KeyedService {
   void DeleteMatchingURLsForKeyword(KeywordID keyword_id,
                                     const base::string16& term);
 
+  // Statistics ----------------------------------------------------------------
+  void HistoryService::CountURLs(size_t* count);
+
   // Bookmarks -----------------------------------------------------------------
 
   // Notification that a URL is no longer bookmarked.