Make PrerenderHandle an observer of PrerenderContents.

chrome/browser/prerender/prerender_unittest.cc

Index: chrome/browser/prerender/prerender_unittest.cc
diff --git a/chrome/browser/prerender/prerender_unittest.cc b/chrome/browser/prerender/prerender_unittest.cc
index 13617a4d8800961dda3b9e3b22a52fb752a45599..b642e60906d39160a32a2706a06c5a62380eec5a 100644
--- a/chrome/browser/prerender/prerender_unittest.cc
+++ b/chrome/browser/prerender/prerender_unittest.cc
@@ -649,13 +649,12 @@ TEST_F(PrerenderTest, PendingPrerenderTest) {
           child_id, route_id, pending_url,
           Referrer(url, WebKit::WebReferrerPolicyDefault), kSize));
   CHECK(pending_prerender_handle.get());
-  EXPECT_TRUE(pending_prerender_handle->IsValid());
-  EXPECT_TRUE(pending_prerender_handle->IsPending());
+  EXPECT_FALSE(pending_prerender_handle->IsValid());
 
   EXPECT_TRUE(prerender_contents->prerendering_has_started());
   ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
 
-  EXPECT_FALSE(pending_prerender_handle->IsPending());
+  EXPECT_TRUE(pending_prerender_handle->IsValid());
   ASSERT_EQ(pending_prerender_contents,
             prerender_manager()->FindAndUseEntry(pending_url));
 }
@@ -686,14 +685,12 @@ TEST_F(PrerenderTest, InvalidPendingPrerenderTest) {
           child_id, route_id, pending_url,
           Referrer(url, WebKit::WebReferrerPolicyDefault), kSize));
   DCHECK(pending_prerender_handle.get());
-  EXPECT_TRUE(pending_prerender_handle->IsValid());
-  EXPECT_TRUE(pending_prerender_handle->IsPending());
+  EXPECT_FALSE(pending_prerender_handle->IsValid());
 
   EXPECT_TRUE(prerender_contents->prerendering_has_started());
   ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
 
   EXPECT_FALSE(pending_prerender_handle->IsValid());
-  EXPECT_FALSE(pending_prerender_handle->IsPending());
 }
 
 TEST_F(PrerenderTest, CancelPendingPrerenderTest) {
@@ -716,13 +713,12 @@ TEST_F(PrerenderTest, CancelPendingPrerenderTest) {
           child_id, route_id, pending_url,
           Referrer(url, WebKit::WebReferrerPolicyDefault), kSize));
   CHECK(pending_prerender_handle.get());
-  EXPECT_TRUE(pending_prerender_handle->IsValid());
-  EXPECT_TRUE(pending_prerender_handle->IsPending());
+  EXPECT_FALSE(pending_prerender_handle->IsValid());
 
   EXPECT_TRUE(prerender_contents->prerendering_has_started());
 
   pending_prerender_handle->OnCancel();
-  EXPECT_FALSE(pending_prerender_handle->IsValid());
+  EXPECT_FALSE(pending_prerender_handle->IsPrerendering());
 
   ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
 }
@@ -839,13 +835,18 @@ TEST_F(PrerenderTest, PPLTLateCancel) {
   prerender_contents->Destroy(FINAL_STATUS_JAVASCRIPT_ALERT);
   ASSERT_EQ(duplicate_prerender_contents, prerender_manager()->FindEntry(url));
 
+  // Surprisingly, OnCancelPrerender isn't expected to do anything because the
+  // PrerenderLinkManager has already removed this prerender.

[mmenke, 2012/12/07 16:46:08]

Doesn't this mess up book keeping?  If the prerender is cancelled, we want to
delete the dummy...

[gavinp, 2012/12/10 17:55:10]

But the PrerenderStop event was sent, and that removed it from the map. The
bookkeeping is already quite messed up once we start sending events down...

The fix is architecturally pretty nasty:
PrerenderManager::MoveEntryToPendingDelete needs to reach into the handle to
reinsert an entry? Or perhaps squash the event through an output parameter?

   prerender_link_manager()->OnCancelPrerender(kDefaultChildId,
                                               last_prerender_id());
+  ASSERT_EQ(duplicate_prerender_contents, prerender_manager()->FindEntry(url));
+
+  // But the PrerenderContents will exist, albiet with no handle.
+  duplicate_prerender_contents->Destroy(FINAL_STATUS_CANCELLED);
   DummyPrerenderContents* null = NULL;
   ASSERT_EQ(null, prerender_manager()->FindEntry(url));
 }
 
-
 // Tests that the prerender manager matches include the fragment.
 TEST_F(PrerenderTest, FragmentMatchesTest) {
   GURL fragment_url("http://www.google.com/#test");
@@ -986,7 +987,6 @@ TEST_F(PrerenderTest, LinkManagerAbandon) {
 
   EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
   ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
-  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
 }
 
 TEST_F(PrerenderTest, LinkManagerCancelTwice) {
@@ -1116,7 +1116,6 @@ TEST_F(PrerenderTest, LinkManagerAddTwiceAbandonTwice) {
   prerender_link_manager()->OnAbandonPrerender(kDefaultChildId,
                                                second_prerender_id);
 
-  EXPECT_TRUE(IsEmptyPrerenderLinkManager());
   EXPECT_FALSE(prerender_contents->prerendering_has_been_cancelled());
   ASSERT_EQ(prerender_contents, prerender_manager()->FindAndUseEntry(url));
 }
@@ -1172,9 +1171,6 @@ TEST_F(PrerenderTest, LinkManagerExpireThenAddAgain) {
   EXPECT_TRUE(second_prerender_contents->prerendering_has_started());
   ASSERT_EQ(second_prerender_contents,
             prerender_manager()->FindAndUseEntry(url));
-  // The PrerenderLinkManager is not empty since we never removed the first
-  // prerender.
-  EXPECT_FALSE(IsEmptyPrerenderLinkManager());
 }
 
 TEST_F(PrerenderTest, LinkManagerCancelThenAddAgain) {
@@ -1200,7 +1196,6 @@ TEST_F(PrerenderTest, LinkManagerCancelThenAddAgain) {
   EXPECT_TRUE(second_prerender_contents->prerendering_has_started());
   ASSERT_EQ(second_prerender_contents,
             prerender_manager()->FindAndUseEntry(url));
-  EXPECT_FALSE(IsEmptyPrerenderLinkManager());
 }
 
 }  // namespace prerender