For prerendering, keep track of all the intermediate redirects, and hook into

the provisional load messages to catch an earlier time to substitute in the
prerendered page.
BUG=none
TEST=search for techcrunch and notice how the preloaded techcrunch.com is used despite the redirect
Review URL: http://codereview.chromium.org/6171007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@71721 0039d316-1c4b-4281-b951-d872f2087c98

8 files changed, 172 insertions, 33 deletions

diff --git a/chrome/browser/prerender/prerender_contents.cc b/chrome/browser/prerender/prerender_contents.cc
index 4970739..c5002f7 100644
--- a/chrome/browser/prerender/prerender_contents.cc
+++ b/chrome/browser/prerender/prerender_contents.cc
@@ -16,18 +16,26 @@
 #include "chrome/common/notification_service.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/common/view_types.h"
+#include "chrome/common/render_messages.h"
 #include "chrome/common/render_messages_params.h"
 #include "gfx/rect.h"
 
 PrerenderContents::PrerenderContents(PrerenderManager* prerender_manager,
                                      Profile* profile,
-                                     const GURL& url)
+                                     const GURL& url,
+                                     const std::vector<GURL>& alias_urls)
     : prerender_manager_(prerender_manager),
       render_view_host_(NULL),
       prerender_url_(url),
       profile_(profile),
       page_id_(0) {
   DCHECK(prerender_manager != NULL);
+  AddAliasURL(prerender_url_);
+  for (std::vector<GURL>::const_iterator it = alias_urls.begin();
+       it != alias_urls.end();
+       ++it) {
+    AddAliasURL(*it);
+  }
 }
 
 void PrerenderContents::StartPrerendering() {
@@ -87,6 +95,8 @@ void PrerenderContents::DidNavigate(
   navigate_params_.reset(p);
 
   url_ = params.url;
+
+  AddAliasURL(url_);
 }
 
 void PrerenderContents::UpdateTitle(RenderViewHost* render_view_host,
@@ -215,3 +225,39 @@ void PrerenderContents::ShowCreatedWidget(int route_id,
 void PrerenderContents::ShowCreatedFullscreenWidget(int route_id) {
   NOTIMPLEMENTED();
 }
+
+bool PrerenderContents::OnMessageReceived(const IPC::Message& message) {
+  bool handled = true;
+  bool message_is_ok = true;
+  IPC_BEGIN_MESSAGE_MAP_EX(PrerenderContents, message, message_is_ok)
+    IPC_MESSAGE_HANDLER(ViewHostMsg_DidStartProvisionalLoadForFrame,
+                        OnDidStartProvisionalLoadForFrame)
+    IPC_MESSAGE_HANDLER(ViewHostMsg_DidRedirectProvisionalLoad,
+                        OnDidRedirectProvisionalLoad)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP_EX()
+
+  return handled;
+}
+
+void PrerenderContents::OnDidStartProvisionalLoadForFrame(int64 frame_id,
+                                                          bool is_main_frame,
+                                                          const GURL& url) {
+  if (is_main_frame)
+    AddAliasURL(url);
+}
+
+void PrerenderContents::OnDidRedirectProvisionalLoad(int32 page_id,
+                                                     const GURL& source_url,
+                                                     const GURL& target_url) {
+  AddAliasURL(target_url);
+}
+
+void PrerenderContents::AddAliasURL(const GURL& url) {
+  alias_urls_.push_back(url);
+}
+
+bool PrerenderContents::MatchesURL(const GURL& url) const {
+  return std::find(alias_urls_.begin(), alias_urls_.end(), url)
+      != alias_urls_.end();
+}
diff --git a/chrome/browser/prerender/prerender_contents.h b/chrome/browser/prerender/prerender_contents.h
index bf2963f..f64697e 100644
--- a/chrome/browser/prerender/prerender_contents.h
+++ b/chrome/browser/prerender/prerender_contents.h
@@ -37,7 +37,7 @@ class PrerenderContents : public RenderViewHostDelegate,
                           public JavaScriptAppModalDialogDelegate {
  public:
   PrerenderContents(PrerenderManager* prerender_manager, Profile* profile,
-                    const GURL& url);
+                    const GURL& url, const std::vector<GURL>& alias_urls);
   virtual ~PrerenderContents();
   virtual void StartPrerendering();
 
@@ -52,6 +52,10 @@ class PrerenderContents : public RenderViewHostDelegate,
   string16 title() const { return title_; }
   int32 page_id() const { return page_id_; }
 
+  // Indicates whether this prerendered page can be used for the provided
+  // URL, i.e. whether there is a match.
+  bool MatchesURL(const GURL& url) const;
+
   // RenderViewHostDelegate implementation.
   virtual RenderViewHostDelegate::View* GetViewDelegate();
   virtual const GURL& GetURL() const;
@@ -133,7 +137,21 @@ class PrerenderContents : public RenderViewHostDelegate,
                                       const std::string& value);
   virtual void ClearInspectorSettings();
 
+ protected:
+  // from RenderViewHostDelegate.
+  virtual bool OnMessageReceived(const IPC::Message& message);
+
  private:
+  // Message handlers.
+  void OnDidStartProvisionalLoadForFrame(int64 frame_id,
+                                         bool main_frame,
+                                         const GURL& url);
+  void OnDidRedirectProvisionalLoad(int32 page_id,
+                                    const GURL& source_url,
+                                    const GURL& target_url);
+
+  void AddAliasURL(const GURL& url);
+
   // The prerender manager owning this object.
   PrerenderManager* prerender_manager_;
 
@@ -162,6 +180,11 @@ class PrerenderContents : public RenderViewHostDelegate,
   GURL url_;
   NotificationRegistrar registrar_;
 
+  // A vector of URLs that this prerendered page matches against.
+  // This array can contain more than element as a result of redirects,
+  // such as HTTP redirects or javascript redirects.
+  std::vector<GURL> alias_urls_;
+
   DISALLOW_COPY_AND_ASSIGN(PrerenderContents);
 };
 
diff --git a/chrome/browser/prerender/prerender_manager.cc b/chrome/browser/prerender/prerender_manager.cc
index 0135880..02a2ac5 100644
--- a/chrome/browser/prerender/prerender_manager.cc
+++ b/chrome/browser/prerender/prerender_manager.cc
@@ -39,7 +39,8 @@ PrerenderManager::~PrerenderManager() {
   }
 }
 
-void PrerenderManager::AddPreload(const GURL& url) {
+void PrerenderManager::AddPreload(const GURL& url,
+                                  const std::vector<GURL>& alias_urls) {
   DCHECK(CalledOnValidThread());
   DeleteOldEntries();
   // If the URL already exists in the set of preloaded URLs, don't do anything.
@@ -49,7 +50,7 @@ void PrerenderManager::AddPreload(const GURL& url) {
     if (it->url_ == url)
       return;
   }
-  PrerenderContentsData data(CreatePrerenderContents(url),
+  PrerenderContentsData data(CreatePrerenderContents(url, alias_urls),
                              GetCurrentTime(), url);
   prerender_list_.push_back(data);
   data.contents_->StartPrerendering();
@@ -75,7 +76,8 @@ PrerenderContents* PrerenderManager::GetEntry(const GURL& url) {
   for (std::list<PrerenderContentsData>::iterator it = prerender_list_.begin();
        it != prerender_list_.end();
        ++it) {
-    if (it->url_ == url) {
+    PrerenderContents* pc = it->contents_;
+    if (pc->MatchesURL(url)) {
       PrerenderContents* pc = it->contents_;
       prerender_list_.erase(it);
       return pc;
@@ -129,6 +131,8 @@ bool PrerenderManager::IsPrerenderElementFresh(const base::Time start) const {
   return (now - start < max_prerender_age_);
 }
 
-PrerenderContents* PrerenderManager::CreatePrerenderContents(const GURL& url) {
-  return new PrerenderContents(this, profile_, url);
+PrerenderContents* PrerenderManager::CreatePrerenderContents(
+    const GURL& url,
+    const std::vector<GURL>& alias_urls) {
+  return new PrerenderContents(this, profile_, url, alias_urls);
 }
diff --git a/chrome/browser/prerender/prerender_manager.h b/chrome/browser/prerender/prerender_manager.h
index 0eff09a..c4a6375 100644
--- a/chrome/browser/prerender/prerender_manager.h
+++ b/chrome/browser/prerender/prerender_manager.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <list>
+#include <vector>
 
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
@@ -26,8 +27,9 @@ class PrerenderManager : public base::RefCounted<PrerenderManager>,
   // Owned by a Profile object for the lifetime of the profile.
   explicit PrerenderManager(Profile* profile);
 
-  // Preloads the URL supplied.
-  void AddPreload(const GURL& url);
+  // Preloads the URL supplied.  alias_urls indicates URLs that redirect
+  // to the same URL to be preloaded.
+  void AddPreload(const GURL& url, const std::vector<GURL>& alias_urls);
 
   // For a given TabContents that wants to navigate to the URL supplied,
   // determines whether a preloaded version of the URL can be used,
@@ -60,7 +62,9 @@ class PrerenderManager : public base::RefCounted<PrerenderManager>,
   bool IsPrerenderElementFresh(const base::Time start) const;
   void DeleteOldEntries();
   virtual base::Time GetCurrentTime() const;
-  virtual PrerenderContents* CreatePrerenderContents(const GURL& url);
+  virtual PrerenderContents* CreatePrerenderContents(
+      const GURL& url,
+      const std::vector<GURL>& alias_urls);
 
   Profile* profile_;
 
diff --git a/chrome/browser/prerender/prerender_manager_unittest.cc b/chrome/browser/prerender/prerender_manager_unittest.cc
index e5cb293..97a573d 100644
--- a/chrome/browser/prerender/prerender_manager_unittest.cc
+++ b/chrome/browser/prerender/prerender_manager_unittest.cc
@@ -13,7 +13,14 @@ namespace {
 class DummyPrerenderContents : public PrerenderContents {
  public:
   DummyPrerenderContents(PrerenderManager* prerender_manager, const GURL& url)
-      : PrerenderContents(prerender_manager, NULL, url),
+      : PrerenderContents(prerender_manager, NULL, url,
+                          std::vector<GURL>()),
+        has_started_(false) {
+  }
+
+  DummyPrerenderContents(PrerenderManager* prerender_manager, const GURL& url,
+                         const std::vector<GURL> alias_urls)
+      : PrerenderContents(prerender_manager, NULL, url, alias_urls),
         has_started_(false) {
   }
 
@@ -43,6 +50,11 @@ class TestPrerenderManager : public PrerenderManager {
     next_pc_.reset(pc);
   }
 
+  // Shorthand to add a simple preload with no aliases.
+  void AddSimplePreload(const GURL& url) {
+    AddPreload(url, std::vector<GURL>());
+  }
+
   PrerenderContents* next_pc() { return next_pc_.get(); }
 
  protected:
@@ -54,7 +66,9 @@ class TestPrerenderManager : public PrerenderManager {
     return time_;
   }
 
-  virtual PrerenderContents* CreatePrerenderContents(const GURL& url) {
+  virtual PrerenderContents* CreatePrerenderContents(
+      const GURL& url,
+      const std::vector<GURL>& alias_urls) {
     return next_pc_.release();
   }
 
@@ -83,7 +97,7 @@ TEST_F(PrerenderManagerTest, FoundTest) {
   DummyPrerenderContents* pc =
       new DummyPrerenderContents(prerender_manager_.get(), url);
   prerender_manager_->SetNextPrerenderContents(pc);
-  prerender_manager_->AddPreload(url);
+  prerender_manager_->AddSimplePreload(url);
   EXPECT_TRUE(pc->has_started());
   EXPECT_EQ(pc, prerender_manager_->GetEntry(url));
   delete pc;
@@ -97,13 +111,13 @@ TEST_F(PrerenderManagerTest, DropSecondRequestTest) {
       new DummyPrerenderContents(prerender_manager_.get(), url);
   DummyPrerenderContents* null = NULL;
   prerender_manager_->SetNextPrerenderContents(pc);
-  prerender_manager_->AddPreload(url);
+  prerender_manager_->AddSimplePreload(url);
   EXPECT_EQ(null, prerender_manager_->next_pc());
   EXPECT_TRUE(pc->has_started());
   DummyPrerenderContents* pc1 =
       new DummyPrerenderContents(prerender_manager_.get(), url);
   prerender_manager_->SetNextPrerenderContents(pc1);
-  prerender_manager_->AddPreload(url);
+  prerender_manager_->AddSimplePreload(url);
   EXPECT_EQ(pc1, prerender_manager_->next_pc());
   EXPECT_FALSE(pc1->has_started());
   EXPECT_EQ(pc, prerender_manager_->GetEntry(url));
@@ -117,7 +131,7 @@ TEST_F(PrerenderManagerTest, ExpireTest) {
       new DummyPrerenderContents(prerender_manager_.get(), url);
   DummyPrerenderContents* null = NULL;
   prerender_manager_->SetNextPrerenderContents(pc);
-  prerender_manager_->AddPreload(url);
+  prerender_manager_->AddSimplePreload(url);
   EXPECT_EQ(null, prerender_manager_->next_pc());
   EXPECT_TRUE(pc->has_started());
   prerender_manager_->AdvanceTime(prerender_manager_->max_prerender_age()
@@ -133,14 +147,14 @@ TEST_F(PrerenderManagerTest, DropOldestRequestTest) {
       new DummyPrerenderContents(prerender_manager_.get(), url);
   DummyPrerenderContents* null = NULL;
   prerender_manager_->SetNextPrerenderContents(pc);
-  prerender_manager_->AddPreload(url);
+  prerender_manager_->AddSimplePreload(url);
   EXPECT_EQ(null, prerender_manager_->next_pc());
   EXPECT_TRUE(pc->has_started());
   GURL url1("http://news.google.com/");
   DummyPrerenderContents* pc1 =
       new DummyPrerenderContents(prerender_manager_.get(), url1);
   prerender_manager_->SetNextPrerenderContents(pc1);
-  prerender_manager_->AddPreload(url1);
+  prerender_manager_->AddSimplePreload(url1);
   EXPECT_EQ(null, prerender_manager_->next_pc());
   EXPECT_TRUE(pc1->has_started());
   EXPECT_EQ(null, prerender_manager_->GetEntry(url));
@@ -157,21 +171,21 @@ TEST_F(PrerenderManagerTest, TwoElementPrerenderTest) {
       new DummyPrerenderContents(prerender_manager_.get(), url);
   DummyPrerenderContents* null = NULL;
   prerender_manager_->SetNextPrerenderContents(pc);
-  prerender_manager_->AddPreload(url);
+  prerender_manager_->AddSimplePreload(url);
   EXPECT_EQ(null, prerender_manager_->next_pc());
   EXPECT_TRUE(pc->has_started());
   GURL url1("http://news.google.com/");
   DummyPrerenderContents* pc1 =
       new DummyPrerenderContents(prerender_manager_.get(),  url1);
   prerender_manager_->SetNextPrerenderContents(pc1);
-  prerender_manager_->AddPreload(url1);
+  prerender_manager_->AddSimplePreload(url1);
   EXPECT_EQ(null, prerender_manager_->next_pc());
   EXPECT_TRUE(pc1->has_started());
   GURL url2("http://images.google.com/");
   DummyPrerenderContents* pc2 =
       new DummyPrerenderContents(prerender_manager_.get(), url2);
   prerender_manager_->SetNextPrerenderContents(pc2);
-  prerender_manager_->AddPreload(url2);
+  prerender_manager_->AddSimplePreload(url2);
   EXPECT_EQ(null, prerender_manager_->next_pc());
   EXPECT_TRUE(pc2->has_started());
   EXPECT_EQ(null, prerender_manager_->GetEntry(url));
@@ -180,3 +194,26 @@ TEST_F(PrerenderManagerTest, TwoElementPrerenderTest) {
   delete pc1;
   delete pc2;
 }
+
+TEST_F(PrerenderManagerTest, AliasURLTest) {
+  GURL url("http://www.google.com/");
+  GURL alias_url1("http://www.google.com/index.html");
+  GURL alias_url2("http://google.com/");
+  GURL not_an_alias_url("http://google.com/index.html");
+  std::vector<GURL> alias_urls;
+  alias_urls.push_back(alias_url1);
+  alias_urls.push_back(alias_url2);
+  DummyPrerenderContents* pc =
+      new DummyPrerenderContents(prerender_manager_.get(), url, alias_urls);
+  prerender_manager_->SetNextPrerenderContents(pc);
+  prerender_manager_->AddSimplePreload(url);
+  EXPECT_EQ(NULL, prerender_manager_->GetEntry(not_an_alias_url));
+  EXPECT_EQ(pc, prerender_manager_->GetEntry(alias_url1));
+  prerender_manager_->SetNextPrerenderContents(pc);
+  prerender_manager_->AddSimplePreload(url);
+  EXPECT_EQ(pc, prerender_manager_->GetEntry(alias_url2));
+  prerender_manager_->SetNextPrerenderContents(pc);
+  prerender_manager_->AddSimplePreload(url);
+  EXPECT_EQ(pc, prerender_manager_->GetEntry(url));
+  delete pc;
+}
diff --git a/chrome/browser/prerender/prerender_resource_handler.cc b/chrome/browser/prerender/prerender_resource_handler.cc
index 507782e..652e89b 100644
--- a/chrome/browser/prerender/prerender_resource_handler.cc
+++ b/chrome/browser/prerender/prerender_resource_handler.cc
@@ -100,8 +100,10 @@ bool PrerenderResourceHandler::OnRequestRedirected(int request_id,
                                                    bool* defer) {
   bool will_redirect = next_handler_->OnRequestRedirected(
       request_id, url, response, defer);
-  if (will_redirect)
+  if (will_redirect) {
+    alias_urls_.push_back(url);
     url_ = url;
+  }
   return will_redirect;
 }
 
@@ -117,7 +119,8 @@ bool PrerenderResourceHandler::OnResponseStarted(int request_id,
         NewRunnableMethod(
             this,
             &PrerenderResourceHandler::RunCallbackFromUIThread,
-            url_));
+            url_,
+            alias_urls_));
   }
   return next_handler_->OnResponseStarted(request_id, response);
 }
@@ -126,8 +129,10 @@ bool PrerenderResourceHandler::OnWillStart(int request_id,
                                            const GURL& url,
                                            bool* defer) {
   bool will_start = next_handler_->OnWillStart(request_id, url, defer);
-  if (will_start)
+  if (will_start) {
+    alias_urls_.push_back(url);
     url_ = url;
+  }
   return will_start;
 }
 
@@ -154,14 +159,18 @@ void PrerenderResourceHandler::OnRequestClosed() {
   next_handler_->OnRequestClosed();
 }
 
-void PrerenderResourceHandler::RunCallbackFromUIThread(const GURL& url) {
+void PrerenderResourceHandler::RunCallbackFromUIThread(const GURL& url,
+                                                       const std::vector<GURL>&
+                                                       alias_urls) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  prerender_callback_->Run(url);
+  prerender_callback_->Run(url, alias_urls);
 }
 
-void PrerenderResourceHandler::StartPrerender(const GURL& url) {
+void PrerenderResourceHandler::StartPrerender(const GURL& url,
+                                              const std::vector<GURL>&
+                                              alias_urls) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-  prerender_manager_->AddPreload(url);
+  prerender_manager_->AddPreload(url, alias_urls);
 }
 
 void PrerenderResourceHandler::set_prerender_duration(base::TimeDelta dt) {
diff --git a/chrome/browser/prerender/prerender_resource_handler.h b/chrome/browser/prerender/prerender_resource_handler.h
index db825e7..b7a36f6 100644
--- a/chrome/browser/prerender/prerender_resource_handler.h
+++ b/chrome/browser/prerender/prerender_resource_handler.h
@@ -71,7 +71,8 @@ class PrerenderResourceHandler : public ResourceHandler {
 
  private:
   friend class PrerenderResourceHandlerTest;
-  typedef Callback1<const GURL&>::Type PrerenderCallback;
+  typedef Callback2<const GURL&, const std::vector<GURL>&>::Type
+      PrerenderCallback;
 
   static const int kDefaultPrerenderDurationSeconds;
 
@@ -81,11 +82,16 @@ class PrerenderResourceHandler : public ResourceHandler {
                            PrerenderCallback* callback);
   virtual ~PrerenderResourceHandler();
 
-  void RunCallbackFromUIThread(const GURL& url);
-  void StartPrerender(const GURL& url);
+  void RunCallbackFromUIThread(const GURL& url,
+                               const std::vector<GURL>& alias_urls);
+  void StartPrerender(const GURL& url,
+                      const std::vector<GURL>& alias_urls);
   void set_prerender_duration(base::TimeDelta prerender_duration);
   void set_get_current_time_function(GetCurrentTimeFunction get_current_time);
 
+  // The set of URLs that are aliases to the URL to be prerendered,
+  // as a result of redirects.
+  std::vector<GURL> alias_urls_;
   GURL url_;
   scoped_refptr<ResourceHandler> next_handler_;
   scoped_refptr<PrerenderManager> prerender_manager_;
diff --git a/chrome/browser/prerender/prerender_resource_handler_unittest.cc b/chrome/browser/prerender/prerender_resource_handler_unittest.cc
index 92ae2e3..110c4cc 100644
--- a/chrome/browser/prerender/prerender_resource_handler_unittest.cc
+++ b/chrome/browser/prerender/prerender_resource_handler_unittest.cc
@@ -100,8 +100,9 @@ class PrerenderResourceHandlerTest : public testing::Test {
     pre_handler_->set_get_current_time_function(&FixedGetCurrentTime);
   }
 
-  void SetLastHandledURL(const GURL& url) {
+  void SetLastHandledURL(const GURL& url, const std::vector<GURL>& alias_urls) {
     last_handled_url_ = url;
+    alias_urls_ = alias_urls;
   }
 
   // Common logic shared by many of the tests
@@ -125,6 +126,12 @@ class PrerenderResourceHandlerTest : public testing::Test {
     loop_.RunAllPending();
   }
 
+  // Test whether a given URL is part of alias_urls_.
+  bool ContainsAliasURL(const GURL& url) {
+    return std::find(alias_urls_.begin(), alias_urls_.end(), url)
+        != alias_urls_.end();
+  }
+
   base::TimeDelta prerender_duration_;
   scoped_refptr<MockResourceHandler> mock_handler_;
   scoped_refptr<PrerenderResourceHandler> pre_handler_;
@@ -132,6 +139,7 @@ class PrerenderResourceHandlerTest : public testing::Test {
   BrowserThread ui_thread_;
   GURL last_handled_url_;
   GURL default_url_;
+  std::vector<GURL> alias_urls_;
 };
 
 namespace {
@@ -208,7 +216,9 @@ TEST_F(PrerenderResourceHandlerTest, PrerenderRedirect) {
   EXPECT_TRUE(last_handled_url_.is_empty());
   loop_.RunAllPending();
   EXPECT_EQ(url_redirect, last_handled_url_);
+  EXPECT_EQ(true, ContainsAliasURL(url_redirect));
+  EXPECT_EQ(true, ContainsAliasURL(default_url_));
+  EXPECT_EQ(2, static_cast<int>(alias_urls_.size()));
 }
 
 }
-