Enable history counting for time ranges.

components/history/core/browser/visit_database.h

Index: components/history/core/browser/visit_database.h
diff --git a/components/history/core/browser/visit_database.h b/components/history/core/browser/visit_database.h
index 765dc81e4871023016ec2253298242de0c843e42..eb3a8f8e59fff716e26db91ab1833bb0363c8c23 100644
--- a/components/history/core/browser/visit_database.h
+++ b/components/history/core/browser/visit_database.h
@@ -178,13 +178,15 @@ class VisitDatabase {
                                   int* count,
                                   base::Time* first_visit);
 
-  // Gets the number of URLs as seen in chrome://history with infinite date
-  // range. "User-visible" is defined as in GetVisibleVisitsInRange() above,
-  // i.e. excluding redirects and subframes. Also, if a URL is visited in
-  // multiple days, the URL is counted once for each day. For determination
-  // of the date, timestamps are converted to dates using local time.
-  // Returns false if there's a failure executing the statement. True otherwise.
-  bool GetHistoryCount(int* count);
+  // Gets the number of URLs as seen in chrome://history within the time
+  // range [|begin_time|, |end_time|). "User-visible" is defined as in
+  // GetVisibleVisitsInRange() above, i.e. excluding redirects and subframes.
+  // Each URL is counted only once per day. For determination of the date,
+  // timestamps are converted to dates using local time. Returns false if
+  // there is a failure executing the statement. True otherwise.
+  bool GetHistoryCount(const base::Time& begin_time,
+                       const base::Time& end_time,
+                       int* count);
 
   // Get the time of the first item in our database.
   bool GetStartDate(base::Time* first_visit);