Coalesce event router Init calls into their constructors.

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

 // Copyright (c) 2012 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.
 
 // Implements the Chrome Extensions WebNavigation API.
 
 #include "chrome/browser/extensions/api/web_navigation/web_navigation_api.h"
 
 #include "base/lazy_instance.h"
 #include "chrome/browser/extensions/api/web_navigation/web_navigation_api_constants.h"
@@ skipping 55 matching lines @@
     : source_web_contents(source_web_contents),
       source_frame_id(source_frame_id),
       source_frame_is_main_frame(source_frame_is_main_frame),
       target_web_contents(target_web_contents),
       target_url(target_url) {
 }
 
 WebNavigationEventRouter::PendingWebContents::~PendingWebContents() {}
 
 WebNavigationEventRouter::WebNavigationEventRouter(Profile* profile)
-    : profile_(profile) {}
-
-WebNavigationEventRouter::~WebNavigationEventRouter() {
-  BrowserList::RemoveObserver(this);
-}
-
-void WebNavigationEventRouter::Init() {
-  if (!registrar_.IsEmpty())
-    return;
+    : profile_(profile) {
+  CHECK(registrar_.IsEmpty());
   registrar_.Add(this,
                  chrome::NOTIFICATION_RETARGETING,
                  content::NotificationService::AllSources());
   registrar_.Add(this,
                  chrome::NOTIFICATION_TAB_ADDED,
                  content::NotificationService::AllSources());
   registrar_.Add(this,
                  content::NOTIFICATION_WEB_CONTENTS_DESTROYED,
                  content::NotificationService::AllSources());
 
   BrowserList::AddObserver(this);
   for (BrowserList::const_iterator iter = BrowserList::begin();
        iter != BrowserList::end(); ++iter) {
     OnBrowserAdded(*iter);
   }
 }
 
+WebNavigationEventRouter::~WebNavigationEventRouter() {
+  BrowserList::RemoveObserver(this);
+}
+
 void WebNavigationEventRouter::OnBrowserAdded(Browser* browser) {
   if (!profile_->IsSameProfile(browser->profile()))
     return;
   browser->tab_strip_model()->AddObserver(this);
 }
 
 void WebNavigationEventRouter::OnBrowserRemoved(Browser* browser) {
   if (!profile_->IsSameProfile(browser->profile()))
     return;
   browser->tab_strip_model()->RemoveObserver(this);
@@ skipping 627 matching lines @@
         parent_frame_id.frame_num);
     frame->process_id = frame_id.render_view_host->GetProcess()->GetID();
     frame->error_occurred = navigation_state.GetErrorOccurredInFrame(frame_id);
     result_list.push_back(frame);
   }
   results_ = GetAllFrames::Results::Create(result_list);
   return true;
 }
 
 }  // namespace extensions