Preserve Page::openedByDOM state across process swaps.

chrome/browser/prerender/prerender_manager.cc

Index: chrome/browser/prerender/prerender_manager.cc
diff --git a/chrome/browser/prerender/prerender_manager.cc b/chrome/browser/prerender/prerender_manager.cc
index 2c5832a4a67ae3752d7aa999c2e262498a4d93ab..541471593e4ebfc1c0058b94ae78dc8d874f6a3b 100644
--- a/chrome/browser/prerender/prerender_manager.cc
+++ b/chrome/browser/prerender/prerender_manager.cc
@@ -529,8 +529,10 @@ WebContents* PrerenderManager::SwapInternal(
     }
   }
 
-  // Do not use the prerendered version if there is an opener object.
-  if (web_contents->HasOpener()) {
+  // Do not use the prerendered version if the target WebContents has an opener
+  // or was created with one. The latter controls whether window.close() is
+  // allowed, so the behavior is observable.
+  if (web_contents->CreatedWithOpener()) {

[Charlie Reis, 2014/04/05 01:41:25]

Unfortunately, using the opener for this was the wrong thing in the first place.
 I mentioned this to cbentzel in http://crbug.com/118294 but I think it got
forgotten.

Prerendering should never be used in tabs with other views in the same
SiteInstance.  Otherwise there are same-origin windows with a reference to the
current tab that will break when it moves to the prerendered process.  The
opener is not the right way to detect this, since it doesn't apply for the
opener itself.

Let's move that fix to a different CL.

[davidben, 2014/04/07 17:57:52]

Hrm, yeah, I'd been wondering if the opener check was a little too lax...

Moving prerender bits out. Also unexposing CreatedWithOpener() outside of
content/ for now. If we end up doing the prerender thing per 118294, it might
not be needed anyway.

     prerender_data->contents()->Destroy(FINAL_STATUS_WINDOW_OPENER);
     return NULL;
   }