Make UnsafeResource hold a WebContents getter instead of RenderFrame ids

chrome/browser/renderer_host/safe_browsing_resource_throttle.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/renderer_host/safe_browsing_resource_throttle.h"
 
 #include <utility>
 
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 244 matching lines @@
   resource.original_url = request_->original_url();
   resource.redirect_urls = redirect_urls_;
   resource.is_subresource = resource_type_ != content::RESOURCE_TYPE_MAIN_FRAME;
   resource.is_subframe = resource_type_ == content::RESOURCE_TYPE_SUB_FRAME;
   resource.threat_type = threat_type;
   resource.threat_metadata = metadata;
   resource.callback = base::Bind(
       &SafeBrowsingResourceThrottle::OnBlockingPageComplete, AsWeakPtr());
   resource.callback_thread = content::BrowserThread::GetTaskRunnerForThread(
       content::BrowserThread::IO);
-  resource.render_process_host_id = info->GetChildID();
-  resource.render_frame_id = info->GetRenderFrameID();
+  resource.web_contents_getter = info->GetWebContentsGetterForRequest();
   resource.threat_source = database_manager_->GetThreatSource();
 
   state_ = STATE_DISPLAYING_BLOCKING_PAGE;
 
   content::BrowserThread::PostTask(
-      content::BrowserThread::UI,
-      FROM_HERE,
+      content::BrowserThread::UI, FROM_HERE,
       base::Bind(&SafeBrowsingResourceThrottle::StartDisplayingBlockingPage,
-                 AsWeakPtr(), ui_manager_, resource));
+                 AsWeakPtr(), ui_manager_, resource, info->GetChildID(),
+                 info->GetRenderFrameID()));
 }
 
 void SafeBrowsingResourceThrottle::StartDisplayingBlockingPage(
     const base::WeakPtr<SafeBrowsingResourceThrottle>& throttle,
     scoped_refptr<SafeBrowsingUIManager> ui_manager,
-    const SafeBrowsingUIManager::UnsafeResource& resource) {
-  content::RenderFrameHost* rfh = content::RenderFrameHost::FromID(
-      resource.render_process_host_id, resource.render_frame_id);
+    const SafeBrowsingUIManager::UnsafeResource& resource,
+    int child_id,
+    int render_frame_id) {
+  content::RenderFrameHost* rfh =
+      content::RenderFrameHost::FromID(child_id, render_frame_id);
   if (rfh) {

[jam, 2016/08/15 19:49:10]

nit: no need to pass in the two IDs, just call the getter here and null check
the WC instead of the RFH

[scottmg, 2016/08/15 19:57:18]

Done.

-    content::WebContents* web_contents =
-        content::WebContents::FromRenderFrameHost(rfh);
+    content::WebContents* web_contents = resource.web_contents_getter.Run();
     prerender::PrerenderContents* prerender_contents =
         prerender::PrerenderContents::FromWebContents(web_contents);
 
     subresource_filter::ContentSubresourceFilterDriverFactory* driver_factory =
         subresource_filter::ContentSubresourceFilterDriverFactory::
             FromWebContents(web_contents);
     DCHECK(driver_factory);
     driver_factory->OnMainResourceMatchedSafeBrowsingBlacklist(
         resource.url, resource.redirect_urls,
         resource.threat_metadata.threat_pattern_type);
@@ skipping 96 matching lines @@
                        unchecked_redirect_url_, "defer_reason",
                        "resumed_redirect");
     }
   }
 
   if (resume) {
     defer_state_ = DEFERRED_NONE;
     controller()->Resume();
   }
 }