Allow top-level navigation in extension pop-ups if it only triggers a download.

chrome/browser/prerender/prerender_contents.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.
 
 #include "chrome/browser/prerender/prerender_contents.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <functional>
@@ skipping 94 matching lines @@
                               const OpenURLParams& params) override {
     // |OpenURLFromTab| is typically called when a frame performs a navigation
     // that requires the browser to perform the transition instead of WebKit.
     // Examples include client redirects to hosted app URLs.
     // TODO(cbentzel): Consider supporting this for CURRENT_TAB dispositions, if
     // it is a common case during prerenders.
     prerender_contents_->Destroy(FINAL_STATUS_OPEN_URL);
     return NULL;
   }
 
-  bool ShouldTransferNavigation() override {
+  bool ShouldTransferNavigation(bool is_main_frame_navigation) override {
     // Cancel the prerender if the navigation attempts to transfer to a
     // different process.  Examples include server redirects to privileged pages
     // or cross-site subframe navigations in --site-per-process.
     prerender_contents_->Destroy(FINAL_STATUS_OPEN_URL);
     return false;
   }
 
   void CloseContents(content::WebContents* contents) override {
     prerender_contents_->Destroy(FINAL_STATUS_CLOSED);
   }
@@ skipping 630 matching lines @@
 void PrerenderContents::AddResourceThrottle(
     const base::WeakPtr<PrerenderResourceThrottle>& throttle) {
   resource_throttles_.push_back(throttle);
 }
 
 void PrerenderContents::AddNetworkBytes(int64_t bytes) {
   network_bytes_ += bytes;
 }
 
 }  // namespace prerender