Make ~WebNavigationEventRouter remove itself from browsers

chrome/browser/extensions/api/web_navigation/web_navigation_api.cc

Index: chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
diff --git a/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc b/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
index 7e2c8db6cd303bd776ce48558961878fbd211a94..ed2e61c379b0d4350b6c526bbbb1c70140dd51ee 100644
--- a/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
+++ b/chrome/browser/extensions/api/web_navigation/web_navigation_api.cc
@@ -91,12 +91,13 @@ WebNavigationEventRouter::WebNavigationEventRouter(Profile* profile)
                  content::NotificationService::AllSources());
 
   BrowserList::AddObserver(this);
-  for (chrome::BrowserIterator it; !it.done(); it.Next()) {
+  for (chrome::BrowserIterator it; !it.done(); it.Next())
     OnBrowserAdded(*it);
-  }
 }
 
 WebNavigationEventRouter::~WebNavigationEventRouter() {
+  for (chrome::BrowserIterator it; !it.done(); it.Next())
+    OnBrowserRemoved(*it);
   BrowserList::RemoveObserver(this);
 }