Don't start prerenders for prerendered pages queued for deletion.

chrome/browser/prerender/prerender_browsertest.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 <deque>
 #include <vector>
 
 #include "base/command_line.h"
 #include "base/path_service.h"
 #include "base/prefs/pref_service.h"
@@ skipping 428 matching lines @@
       PrerenderManager* prerender_manager,
       Profile* profile,
       const GURL& url,
       const content::Referrer& referrer,
       Origin origin,
       uint8 experiment_id) OVERRIDE {
     FinalStatus expected_final_status = FINAL_STATUS_MAX;
     if (!expected_final_status_queue_.empty()) {
       expected_final_status = expected_final_status_queue_.front();
       expected_final_status_queue_.pop_front();
+    } else {
+      // There shouldn't be any unexpected prerenders.
+      ADD_FAILURE() << "Unexpected prerender attempt";
     }
     VLOG(1) << "Creating prerender contents for " << url.path() <<
                " with expected final status " << expected_final_status;
     VLOG(1) << expected_final_status_queue_.size() << " left in the queue.";
     return new TestPrerenderContents(prerender_manager,
                                      profile, url, referrer, origin,
                                      expected_number_of_loads_,
                                      expected_final_status,
                                      prerender_should_wait_for_ready_title_);
   }
@@ skipping 1995 matching lines @@
 
   MessageLoop::current()->PostTask(
       FROM_HERE, base::Bind(&CancelAllPrerenders, GetPrerenderManager()));
   content::RunMessageLoop();
 
   EXPECT_TRUE(DidReceivePrerenderStartEventForLinkNumber(0));
   EXPECT_TRUE(DidReceivePrerenderStopEventForLinkNumber(0));
   EXPECT_FALSE(HadPrerenderEventErrors());
 }
 
+// Cancels the prerender of a page with its own prerender.  The second prerender
+// should never be started.
+IN_PROC_BROWSER_TEST_F(PrerenderBrowserTest,
+                       PrerenderCancelPrerenderWithPrerender) {
+  PrerenderTestURL("files/prerender/prerender_infinite_a.html",
+                   FINAL_STATUS_CANCELLED,
+                   1);
+  // Post a task to cancel all the prerenders.
+  MessageLoop::current()->PostTask(
+      FROM_HERE, base::Bind(&CancelAllPrerenders, GetPrerenderManager()));
+  content::RunMessageLoop();
+  EXPECT_TRUE(GetPrerenderContents() == NULL);
+}
+
 // PrerenderBrowserTest.PrerenderEventsNoLoad may pass flakily on regression,
 // so please be aggressive about filing bugs when this test is failing.
 IN_PROC_BROWSER_TEST_F(PrerenderBrowserTest, PrerenderEventsNoLoad) {
   // This should be canceled.
   PrerenderTestURL("files/prerender/prerender_http_auth_container.html",
                    FINAL_STATUS_AUTH_NEEDED,
                    1);
   EXPECT_TRUE(DidReceivePrerenderStartEventForLinkNumber(0));
   EXPECT_FALSE(DidReceivePrerenderLoadEventForLinkNumber(0));
   EXPECT_FALSE(DidReceivePrerenderStopEventForLinkNumber(0));
@@ skipping 251 matching lines @@
   channel_close_watcher.WatchChannel(browser()->tab_strip_model()->
       GetActiveWebContents()->GetRenderProcessHost());
   NavigateToDestURL();
   channel_close_watcher.WaitForChannelClose();
 
   ASSERT_TRUE(IsEmptyPrerenderLinkManager());
   ASSERT_TRUE(catcher.GetNextResult()) << catcher.message();
 }
 
 }  // namespace prerender