Make UnsafeResource hold a WebContents getter instead of RenderFrame ids

chrome/browser/renderer_host/safe_browsing_resource_throttle.cc

Index: chrome/browser/renderer_host/safe_browsing_resource_throttle.cc
diff --git a/chrome/browser/renderer_host/safe_browsing_resource_throttle.cc b/chrome/browser/renderer_host/safe_browsing_resource_throttle.cc
index 54f7a85d8d5ca713886cc7c3c0685f5e207551e1..ffa6912e981849c01bdd9cbdf810d9280c40e0ed 100644
--- a/chrome/browser/renderer_host/safe_browsing_resource_throttle.cc
+++ b/chrome/browser/renderer_host/safe_browsing_resource_throttle.cc
@@ -262,28 +262,28 @@ void SafeBrowsingResourceThrottle::OnCheckBrowseUrlResult(
       &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);