Creates BrowserTabStripTracker to consolidate common code

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

Index: chrome/browser/extensions/api/tabs/tabs_event_router.h
diff --git a/chrome/browser/extensions/api/tabs/tabs_event_router.h b/chrome/browser/extensions/api/tabs/tabs_event_router.h
index 1c6a9eb3358c0f269e36ebd6a6d9c3c25150740d..fb1dd5452ed0af31b460ab9db3ec94f2188872bb 100644
--- a/chrome/browser/extensions/api/tabs/tabs_event_router.h
+++ b/chrome/browser/extensions/api/tabs/tabs_event_router.h
@@ -14,6 +14,8 @@
 #include "base/scoped_observer.h"
 #include "chrome/browser/extensions/api/tabs/tabs_api.h"
 #include "chrome/browser/ui/browser_list_observer.h"
+#include "chrome/browser/ui/browser_tab_strip_tracker.h"
+#include "chrome/browser/ui/browser_tab_strip_tracker_delegate.h"
 #include "chrome/browser/ui/tabs/tab_strip_model_observer.h"
 #include "components/favicon/core/favicon_driver_observer.h"
 #include "components/ui/zoom/zoom_observer.h"
@@ -35,6 +37,7 @@ namespace extensions {
 // TabsEventRouter will only route events from windows/tabs within a profile to
 // extension processes in the same profile.
 class TabsEventRouter : public TabStripModelObserver,
+                        public BrowserTabStripTrackerDelegate,
                         public chrome::BrowserListObserver,
                         public content::NotificationObserver,
                         public favicon::FaviconDriverObserver,
@@ -43,9 +46,10 @@ class TabsEventRouter : public TabStripModelObserver,
   explicit TabsEventRouter(Profile* profile);
   ~TabsEventRouter() override;
 
+  // BrowserTabStripTrackerDelegate:
+  bool ShouldTrackBrowser(Browser* browser) override;
+
   // chrome::BrowserListObserver

[Peter Kasting, 2015/10/10 00:34:39]

Nit: While here: Colons on these class names?

[sky, 2015/10/12 15:16:21]

Done.

-  void OnBrowserAdded(Browser* browser) override;
-  void OnBrowserRemoved(Browser* browser) override;
   void OnBrowserSetLastActive(Browser* browser) override;
 
   // TabStripModelObserver
@@ -124,10 +128,6 @@ class TabsEventRouter : public TabStripModelObserver,
       scoped_ptr<base::DictionaryValue> changed_properties);
 
   // Register ourselves to receive the various notifications we are interested
-  // in for a browser.
-  void RegisterForBrowserNotifications(Browser* browser);
-
-  // Register ourselves to receive the various notifications we are interested
   // in for a tab.
   void RegisterForTabNotifications(content::WebContents* contents);
 
@@ -197,6 +197,8 @@ class TabsEventRouter : public TabStripModelObserver,
   ScopedObserver<favicon::FaviconDriver, TabsEventRouter>
       favicon_scoped_observer_;
 
+  BrowserTabStripTracker browser_tab_strip_tracker_;
+
   DISALLOW_COPY_AND_ASSIGN(TabsEventRouter);
 };