components/sync_driver/revisit/current_tab_matcher.cc

   1 // Copyright 2015 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "components/sync_driver/revisit/current_tab_matcher.h"
   6
   7 #include "base/metrics/histogram_macros.h"
   8 #include "base/time/time.h"
   9 #include "components/sessions/serialized_navigation_entry.h"
  10
  11 namespace sync_driver {
  12
  13 CurrentTabMatcher::CurrentTabMatcher(const PageEquality& page_equality)
  14     : page_equality_(page_equality) {}
  15
  16 void CurrentTabMatcher::Check(const sessions::SessionTab* tab) {
  17   if (tab->navigations.empty()) {
  18     return;
  19   }
  20   const sessions::SerializedNavigationEntry& currentEntry =
  21       tab->navigations[tab->normalized_navigation_index()];
  22   // Cannot rely on SerializedNavigationEntry timestamps, they're
  23   // not set for foreign sessions. Instead rely on tab timestamps.
  24   if (page_equality_.IsSamePage(currentEntry.virtual_url()) &&
  25       (most_recent_match_ == nullptr ||
  26        tab->timestamp > most_recent_match_->timestamp)) {
  27     most_recent_match_ = tab;
  28   }
  29 }
  30
  31 void CurrentTabMatcher::Emit(
  32     const PageVisitObserver::TransitionType transition) {
  33   if (most_recent_match_ == nullptr) {
  34     UMA_HISTOGRAM_ENUMERATION("Sync.PageRevisitTabMissTransition", transition,
  35                               PageVisitObserver::kTransitionTypeLast);
  36   } else {
  37     base::TimeDelta age(base::Time::Now() - most_recent_match_->timestamp);
  38     UMA_HISTOGRAM_CUSTOM_TIMES("Sync.PageRevisitTabMatchAge", age,
  39                                base::TimeDelta::FromSeconds(1),
  40                                base::TimeDelta::FromDays(14), 100);
  41     UMA_HISTOGRAM_ENUMERATION("Sync.PageRevisitTabMatchTransition", transition,
  42                               PageVisitObserver::kTransitionTypeLast);
  43   }
  44 }
  45
  46 }  // namespace sync_driver