Cancel prerender when we discover a download starting from a page we are prer...

chrome/browser/prerender/prerender_contents.cc

Index: chrome/browser/prerender/prerender_contents.cc
===================================================================
--- chrome/browser/prerender/prerender_contents.cc	(revision 74377)
+++ chrome/browser/prerender/prerender_contents.cc	(working copy)
@@ -11,6 +11,7 @@
 #include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/renderer_host/render_view_host.h"
+#include "chrome/browser/renderer_host/resource_request_details.h"
 #include "chrome/browser/renderer_host/site_instance.h"
 #include "chrome/browser/renderer_preferences_util.h"
 #include "chrome/browser/ui/login/login_prompt.h"
@@ -82,6 +83,10 @@
   registrar_.Add(this, NotificationType::AUTH_CANCELLED,
                  NotificationService::AllSources());
 
+  // Register all responses to see if we should cancel.
+  registrar_.Add(this, NotificationType::DOWNLOAD_INITIATED,
+                 Source<RenderViewHostDelegate>(this));
+
   DCHECK(load_start_time_.is_null());
   load_start_time_ = base::TimeTicks::Now();
 
@@ -95,6 +100,7 @@
 void PrerenderContents::set_final_status(FinalStatus final_status) {
   DCHECK(final_status >= FINAL_STATUS_USED && final_status < FINAL_STATUS_MAX);
   DCHECK_EQ(FINAL_STATUS_MAX, final_status_);
+
   final_status_ = final_status;
 }
 
@@ -186,6 +192,7 @@
     case NotificationType::PROFILE_DESTROYED:
       Destroy(FINAL_STATUS_PROFILE_DESTROYED);
       return;
+
     case NotificationType::APP_TERMINATING:
       Destroy(FINAL_STATUS_APP_TERMINATING);
       return;
@@ -201,11 +208,22 @@
       LoginHandler* handler = details_ptr->handler();
       DCHECK(handler != NULL);
       RenderViewHostDelegate* delegate = handler->GetRenderViewHostDelegate();
-      if (controller == NULL && delegate == this)
+      if (controller == NULL && delegate == this) {
         Destroy(FINAL_STATUS_AUTH_NEEDED);
+        return;
+      }
       break;
     }
 
+    case NotificationType::DOWNLOAD_INITIATED: {
+      // If the download is started from a RenderViewHost that we are
+      // delegating, kill the prerender. This will also stop the download and

[Randy Smith (Not in Mondays), 2011/02/10 16:57:10]

Can you give me the context for how killing the prerender stops the download?  I
thought that the download never got started because the limiter blocked it.

[dominich, 2011/02/10 18:46:22]

You're right - changed the comment to reflect that.

When the prerender is cancelled, the RenderViewHost is shutdown and deleted and
unless I've missed something this cancels all requests made from that
RenderViewHost.

Done.

+      // navigating to the page will restart it as expected.
+      DCHECK(Source<RenderViewHostDelegate>(source).ptr() == this);
+      Destroy(FINAL_STATUS_DOWNLOAD);
+      return;
+    }
+
     default:
       NOTREACHED() << "Unexpected notification sent.";
       break;