Ensure that PageID's of prerendered pages do not exceed the Page ID of the

chrome/browser/prerender/prerender_manager.cc

 // Copyright (c) 2011 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_manager.h"
 
 #include <string>
 
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
@@ skipping 526 matching lines @@
   if (prerender_contents.get() == NULL)
     return false;
 
   // Do not use the prerendered version if the opener window.property was
   // supposed to be set.
   if (has_opener_set) {
     prerender_contents.release()->Destroy(FINAL_STATUS_WINDOW_OPENER);
     return false;
   }
 
+  if (prerender_contents->starting_page_id() <=

[dominich, 2011/05/23 17:05:15]

Add a comment explaining this check.

+      tab_contents->GetMaxPageID()) {
+    prerender_contents.release()->Destroy(FINAL_STATUS_PAGE_ID_CONFLICT);
+    return false;
+  }
+
   // If we are just in the control group (which can be detected by noticing
   // that prerendering hasn't even started yet), record that |tab_contents| now
   // would be showing a prerendered contents, but otherwise, don't do anything.
   if (!prerender_contents->prerendering_has_started()) {
     MarkTabContentsAsWouldBePrerendered(tab_contents);
     return false;
   }
 
   int child_id, route_id;
   CHECK(prerender_contents->GetChildId(&child_id));
@@ skipping 437 matching lines @@
   base::TimeTicks cutoff = GetCurrentTimeTicks() -
       base::TimeDelta::FromMilliseconds(kNavigationRecordWindowMs);
   while (!navigations_.empty()) {
     if (navigations_.front().time_ > cutoff)
       break;
     navigations_.pop_front();
   }
 }
 
 }  // namespace prerender