Handle online and offline redirects via interceptor and offline scheme

chrome/browser/android/offline_pages/offline_page_tab_helper.cc

 // Copyright 2016 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/android/offline_pages/offline_page_tab_helper.h"
 
 #include "base/bind.h"
 #include "base/logging.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/histogram.h"
@@ skipping 65 matching lines @@
 
   // This is a new navigation so we can invalidate any previously scheduled
   // operations.
   weak_ptr_factory_.InvalidateWeakPtrs();
 
   // Since this is a new navigation, we will reset the cached offline page,
   // unless we are currently looking at an offline page.
   GURL navigated_url = navigation_handle->GetURL();
   if (offline_page_ && navigated_url != offline_page_->GetOfflineURL())
     offline_page_ = nullptr;
-
-  // Ignore navigations that are forward or back transitions in the nav stack
-  // which are not at the head of the stack.
-  // TODO(dimich): Not sure this is needed. Clarify and remove. Bug 624216.
-  const content::NavigationController& controller =
-      web_contents()->GetController();
-  if (controller.GetEntryCount() > 0 &&
-      controller.GetCurrentEntryIndex() != -1 &&
-      controller.GetCurrentEntryIndex() < controller.GetEntryCount() - 1) {
-    return;
-  }
-
-  content::BrowserContext* context = web_contents()->GetBrowserContext();
-  if (net::NetworkChangeNotifier::IsOffline()) {
-    GetPagesForRedirectToOffline(
-        RedirectResult::REDIRECTED_ON_DISCONNECTED_NETWORK, navigated_url);
-    return;
-  }
-
-  OfflinePageModel* offline_page_model =
-      OfflinePageModelFactory::GetForBrowserContext(context);
-  if (!offline_page_model)
-    return;
-
-  offline_page_model->GetPageByOfflineURL(
-      navigated_url, base::Bind(&OfflinePageTabHelper::RedirectToOnline,
-                                weak_ptr_factory_.GetWeakPtr(), navigated_url));
 }
 
 void OfflinePageTabHelper::DidFinishNavigation(
     content::NavigationHandle* navigation_handle) {
   // Skips non-main frame.
   if (!navigation_handle->IsInMainFrame())
     return;
 
   GURL navigated_url = navigation_handle->GetURL();
   net::Error error_code = navigation_handle->GetNetErrorCode();
@@ skipping 143 matching lines @@
          !entry->GetRedirectChain().empty() &&
          entry->GetRedirectChain().back() == to_url;
 }
 
 void OfflinePageTabHelper::ReportRedirectResultUMA(RedirectResult result) {
   UMA_HISTOGRAM_ENUMERATION("OfflinePages.RedirectResult",
       static_cast<int>(result),
       static_cast<int>(RedirectResult::REDIRECT_RESULT_MAX));
 }
 }  // namespace offline_pages