Add metrics to keep track of the tab activate/deactivate cycle

chrome/browser/extensions/api/tabs/tabs_event_router.cc

 // Copyright 2013 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 "chrome/browser/extensions/api/tabs/tabs_event_router.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <utility>
@@ skipping 199 matching lines @@
       events::TABS_ON_CREATED, tabs::OnCreated::kEventName, std::move(args)));
   event->restrict_to_browser_context = profile;
   event->user_gesture = EventRouter::USER_GESTURE_NOT_ENABLED;
   event->will_dispatch_callback =
       base::Bind(&WillDispatchTabCreatedEvent, contents, active);
   EventRouter::Get(profile)->BroadcastEvent(std::move(event));
 
   RegisterForTabNotifications(contents);
 }
 
-void TabsEventRouter::TabInsertedAt(WebContents* contents,
+void TabsEventRouter::TabInsertedAt(TabStripModel* tab_strip_model,
+                                    WebContents* contents,
                                     int index,
                                     bool active) {
   if (!GetTabEntry(contents)) {
     // We've never seen this tab, send create event as long as we're not in the
     // constructor.
     if (browser_tab_strip_tracker_.is_processing_initial_browsers())
       RegisterForTabNotifications(contents);
     else
       TabCreatedAt(contents, index, active);
     return;
@@ skipping 268 matching lines @@
   DispatchEvent(Profile::FromBrowserContext(new_contents->GetBrowserContext()),
                 events::TABS_ON_REPLACED, tabs::OnReplaced::kEventName,
                 std::move(args), EventRouter::USER_GESTURE_UNKNOWN);
 
   UnregisterForTabNotifications(old_contents);
 
   if (!GetTabEntry(new_contents))
     RegisterForTabNotifications(new_contents);
 }
 
-void TabsEventRouter::TabPinnedStateChanged(WebContents* contents, int index) {
+void TabsEventRouter::TabPinnedStateChanged(TabStripModel* tab_strip_model,
+                                            WebContents* contents,
+                                            int index) {
   TabStripModel* tab_strip = NULL;
   int tab_index;
 
   if (ExtensionTabUtil::GetTabStripModel(contents, &tab_strip, &tab_index)) {
     std::set<std::string> changed_property_names;
     changed_property_names.insert(tabs_constants::kPinnedKey);
     DispatchTabUpdatedEvent(contents, std::move(changed_property_names));
   }
 }
 
@@ skipping 54 matching lines @@
   int tab_index = -1;
 
   if (ExtensionTabUtil::GetTabStripModel(contents, &tab_strip, &tab_index)) {
     std::set<std::string> changed_property_names;
     changed_property_names.insert(tabs_constants::kAutoDiscardableKey);
     DispatchTabUpdatedEvent(contents, std::move(changed_property_names));
   }
 }
 
 }  // namespace extensions