Clear prerender history on clear history.

Also cancel active prerenders on clear history or cache.

BUG=none
TEST=PrerenderManagerTest.ClearTest, PrerenderHistoryTest.GetAsValue, PrerenderBrowserTest.PrerenderClearHistory, PrerenderBrowserTest.PrerenderClearCache

Review URL: http://codereview.chromium.org/7205007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@89729 0039d316-1c4b-4281-b951-d872f2087c98

11 files changed, 173 insertions, 16 deletions

diff --git a/chrome/browser/browsing_data_remover.cc b/chrome/browser/browsing_data_remover.cc
index 74e294c9..9a42c40 100644
--- a/chrome/browser/browsing_data_remover.cc
+++ b/chrome/browser/browsing_data_remover.cc
@@ -21,6 +21,7 @@
 #include "chrome/browser/net/chrome_url_request_context.h"
 #include "chrome/browser/password_manager/password_store.h"
 #include "chrome/browser/plugin_data_remover.h"
+#include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/renderer_host/web_cache_manager.h"
 #include "chrome/browser/search_engines/template_url_service.h"
@@ -173,6 +174,17 @@ void BrowsingDataRemover::Remove(int remove_mask) {
         SessionServiceFactory::GetForProfile(profile_);
     if (session_service)
       session_service->DeleteLastSession();
+
+    // The PrerenderManager keeps history of prerendered pages, so clear that.
+    // It also may have a prerendered page. If so, the page could be considered
+    // to have a small amount of historical information, so delete it, too.
+    prerender::PrerenderManager* prerender_manager =
+        profile_->GetPrerenderManager();
+    if (prerender_manager) {
+      prerender_manager->ClearData(
+          prerender::PrerenderManager::CLEAR_PRERENDER_CONTENTS |
+          prerender::PrerenderManager::CLEAR_PRERENDER_HISTORY);
+    }
   }
 
   if (remove_mask & REMOVE_DOWNLOADS) {
@@ -281,6 +293,15 @@ void BrowsingDataRemover::Remove(int remove_mask) {
     BrowserThread::PostTask(
         BrowserThread::IO, FROM_HERE,
         NewRunnableMethod(this, &BrowsingDataRemover::ClearCacheOnIOThread));
+
+    // The PrerenderManager may have a page actively being prerendered, which
+    // is essentially a preemptively cached page.
+    prerender::PrerenderManager* prerender_manager =
+        profile_->GetPrerenderManager();
+    if (prerender_manager) {
+      prerender_manager->ClearData(
+          prerender::PrerenderManager::CLEAR_PRERENDER_CONTENTS);
+    }
   }
 
   if (remove_mask & REMOVE_LSO_DATA) {
diff --git a/chrome/browser/browsing_data_remover.h b/chrome/browser/browsing_data_remover.h
index 428cb9b..fbfd4ec 100644
--- a/chrome/browser/browsing_data_remover.h
+++ b/chrome/browser/browsing_data_remover.h
@@ -50,15 +50,16 @@ class BrowsingDataRemover : public NotificationObserver,
   };
 
   // Mask used for Remove.
-
-  // In addition to visits, this removes keywords and the last session.
-  static const int REMOVE_HISTORY = 1 << 0;
-  static const int REMOVE_DOWNLOADS = 1 << 1;
-  static const int REMOVE_COOKIES = 1 << 2;
-  static const int REMOVE_PASSWORDS = 1 << 3;
-  static const int REMOVE_FORM_DATA = 1 << 4;
-  static const int REMOVE_CACHE = 1 << 5;
-  static const int REMOVE_LSO_DATA = 1 << 6;
+  enum RemoveDataMask {
+    // In addition to visits, this removes keywords and the last session.
+    REMOVE_HISTORY = 1 << 0,
+    REMOVE_DOWNLOADS = 1 << 1,
+    REMOVE_COOKIES = 1 << 2,
+    REMOVE_PASSWORDS = 1 << 3,
+    REMOVE_FORM_DATA = 1 << 4,
+    REMOVE_CACHE = 1 << 5,
+    REMOVE_LSO_DATA = 1 << 6,
+  };
 
   // Observer is notified when the removal is done. Done means keywords have
   // been deleted, cache cleared and all other tasks scheduled.
diff --git a/chrome/browser/prerender/prerender_browsertest.cc b/chrome/browser/prerender/prerender_browsertest.cc
index f30a5eb..f1dec03 100644
--- a/chrome/browser/prerender/prerender_browsertest.cc
+++ b/chrome/browser/prerender/prerender_browsertest.cc
@@ -8,7 +8,9 @@
 #include "base/path_service.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
+#include "base/values.h"
 #include "base/test/test_timeouts.h"
+#include "chrome/browser/browsing_data_remover.h"
 #include "chrome/browser/content_settings/host_content_settings_map.h"
 #include "chrome/browser/favicon/favicon_tab_helper.h"
 #include "chrome/browser/prefs/pref_service.h"
@@ -58,6 +60,16 @@ std::string CreateServerRedirect(const std::string& dest_url) {
   return kServerRedirectBase + dest_url;
 }
 
+// Clears the specified data using BrowsingDataRemover.
+void ClearBrowsingData(Browser* browser, int remove_mask) {
+  BrowsingDataRemover* remover =
+      new BrowsingDataRemover(browser->profile(),
+                              BrowsingDataRemover::EVERYTHING,
+                              base::Time());
+  remover->Remove(remove_mask);
+  // BrowsingDataRemover deletes itself.
+}
+
 // Returns true if and only if the final status is one in which the prerendered
 // page should prerender correctly. The page still may not be used.
 bool ShouldRenderPrerenderedPageCorrectly(FinalStatus status) {
@@ -65,6 +77,7 @@ bool ShouldRenderPrerenderedPageCorrectly(FinalStatus status) {
     case FINAL_STATUS_USED:
     case FINAL_STATUS_WINDOW_OPENER:
     case FINAL_STATUS_FRAGMENT_MISMATCH:
+    case FINAL_STATUS_CACHE_OR_HISTORY_CLEARED:
     // We'll crash the renderer after it's loaded.
     case FINAL_STATUS_RENDERER_CRASHED:
       return true;
@@ -468,6 +481,18 @@ class PrerenderBrowserTest : public InProcessBrowserTest {
     return prerender_manager;
   }
 
+  // Returns length of |prerender_manager_|'s history, or -1 on failure.
+  int GetHistoryLength() const {
+    scoped_ptr<DictionaryValue> prerender_dict(
+        static_cast<DictionaryValue*>(prerender_manager()->GetAsValue()));
+    if (!prerender_dict.get())
+      return -1;
+    ListValue* history_list;
+    if (!prerender_dict->GetList("history", &history_list))
+      return -1;
+    return static_cast<int>(history_list->GetSize());
+  }
+
   FakeSafeBrowsingService* GetSafeBrowsingService() {
     return safe_browsing_factory_->most_recent_service();
   }
@@ -1391,4 +1416,42 @@ IN_PROC_BROWSER_TEST_F(PrerenderBrowserTest, PrerenderUnload) {
   EXPECT_TRUE(title_watcher.Wait());
 }
 
+// Checks that when the history is cleared, prerendering is cancelled and
+// prerendering history is cleared.
+// DISABLED: http://www.crbug.com/86829
+IN_PROC_BROWSER_TEST_F(PrerenderBrowserTest, DISABLED_PrerenderClearHistory) {
+  PrerenderTestURL("files/prerender/prerender_page.html",
+                   FINAL_STATUS_CACHE_OR_HISTORY_CLEARED,
+                   1);
+
+  // Post a task to clear the history, and run the message loop until it
+  // destroys the prerender.
+  MessageLoop::current()->PostTask(FROM_HERE,
+      NewRunnableFunction(ClearBrowsingData, browser(),
+                          BrowsingDataRemover::REMOVE_HISTORY));
+  ui_test_utils::RunMessageLoop();
+
+  // Make sure prerender history was cleared.
+  EXPECT_EQ(0, GetHistoryLength());
+}
+
+// Checks that when the cache is cleared, prerenders are cancelled but
+// prerendering history is not cleared.
+IN_PROC_BROWSER_TEST_F(PrerenderBrowserTest, PrerenderClearCache) {
+  PrerenderTestURL("files/prerender/prerender_page.html",
+                   FINAL_STATUS_CACHE_OR_HISTORY_CLEARED,
+                   1);
+
+  // Post a task to clear the cache, and run the message loop until it
+  // destroys the prerender.
+  MessageLoop::current()->PostTask(FROM_HERE,
+      NewRunnableFunction(ClearBrowsingData, browser(),
+                          BrowsingDataRemover::REMOVE_CACHE));
+  ui_test_utils::RunMessageLoop();
+
+  // Make sure prerender history was not cleared.  Not a vital behavior, but
+  // used to compare with PrerenderClearHistory test.
+  EXPECT_EQ(1, GetHistoryLength());
+}
+
 }  // namespace prerender
diff --git a/chrome/browser/prerender/prerender_final_status.cc b/chrome/browser/prerender/prerender_final_status.cc
index 50f57d0..8d71e41 100644
--- a/chrome/browser/prerender/prerender_final_status.cc
+++ b/chrome/browser/prerender/prerender_final_status.cc
@@ -43,6 +43,7 @@ const char* kFinalStatusNames[] = {
   "Safe Browsing",
   "Fragment Mismatch",
   "SSL Client Certificate Requested",
+  "Cache or History Cleared",
   "Max",
 };
 COMPILE_ASSERT(arraysize(kFinalStatusNames) == FINAL_STATUS_MAX + 1,
diff --git a/chrome/browser/prerender/prerender_final_status.h b/chrome/browser/prerender/prerender_final_status.h
index 79afc23..da9fec8 100644
--- a/chrome/browser/prerender/prerender_final_status.h
+++ b/chrome/browser/prerender/prerender_final_status.h
@@ -41,6 +41,7 @@ enum FinalStatus {
   FINAL_STATUS_SAFE_BROWSING = 28,
   FINAL_STATUS_FRAGMENT_MISMATCH = 29,
   FINAL_STATUS_SSL_CLIENT_CERTIFICATE_REQUESTED = 30,
+  FINAL_STATUS_CACHE_OR_HISTORY_CLEARED = 31,
   FINAL_STATUS_MAX,
 };
 
diff --git a/chrome/browser/prerender/prerender_history.cc b/chrome/browser/prerender/prerender_history.cc
index 319af90..1f2e16c 100644
--- a/chrome/browser/prerender/prerender_history.cc
+++ b/chrome/browser/prerender/prerender_history.cc
@@ -24,6 +24,10 @@ void PrerenderHistory::AddEntry(const Entry& entry) {
   entries_.push_back(entry);
 }
 
+void PrerenderHistory::Clear() {
+  entries_.clear();
+}
+
 Value* PrerenderHistory::GetEntriesAsValue() const {
   ListValue* return_list = new ListValue();
   for (std::list<Entry>::const_reverse_iterator it = entries_.rbegin();
diff --git a/chrome/browser/prerender/prerender_history.h b/chrome/browser/prerender/prerender_history.h
index 1754c2b..5bc009f 100644
--- a/chrome/browser/prerender/prerender_history.h
+++ b/chrome/browser/prerender/prerender_history.h
@@ -47,6 +47,9 @@ class PrerenderHistory : public base::NonThreadSafe {
   // Adds |entry| to the history. If at capacity, the oldest entry is dropped.
   void AddEntry(const Entry& entry);
 
+  // Deletes all history entries.
+  void Clear();
+
   // Retrieves the entries as a value which can be displayed.
   Value* GetEntriesAsValue() const;
 
diff --git a/chrome/browser/prerender/prerender_history_unittest.cc b/chrome/browser/prerender/prerender_history_unittest.cc
index d37e821..f28dde4 100644
--- a/chrome/browser/prerender/prerender_history_unittest.cc
+++ b/chrome/browser/prerender/prerender_history_unittest.cc
@@ -82,6 +82,13 @@ TEST(PrerenderHistoryTest, GetAsValue)  {
   EXPECT_EQ(2u, entry_list->GetSize());
   EXPECT_TRUE(ListEntryMatches(entry_list, 0u, kThirdUrl, kThirdFinalStatus));
   EXPECT_TRUE(ListEntryMatches(entry_list, 1u, kSecondUrl, kSecondFinalStatus));
+
+  // Make sure clearing history acts as expected.
+  history.Clear();
+  entry_value.reset(history.GetEntriesAsValue());
+  ASSERT_TRUE(entry_value.get() != NULL);
+  ASSERT_TRUE(entry_value->GetAsList(&entry_list));
+  EXPECT_TRUE(entry_list->empty());
 }
 
 }  // namespace
diff --git a/chrome/browser/prerender/prerender_manager.cc b/chrome/browser/prerender/prerender_manager.cc
index f4f4a31..9d79e4a 100644
--- a/chrome/browser/prerender/prerender_manager.cc
+++ b/chrome/browser/prerender/prerender_manager.cc
@@ -10,6 +10,7 @@
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "base/time.h"
+#include "base/values.h"
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/favicon/favicon_tab_helper.h"
@@ -266,13 +267,7 @@ PrerenderManager::PrerenderManager(Profile* profile,
 }
 
 PrerenderManager::~PrerenderManager() {
-  DeleteOldTabContents();
-  while (!prerender_list_.empty()) {
-    PrerenderContentsData data = prerender_list_.front();
-    prerender_list_.pop_front();
-    data.contents_->Destroy(FINAL_STATUS_MANAGER_SHUTDOWN);
-  }
-  DeletePendingDeleteEntries();
+  DestroyAllContents(FINAL_STATUS_MANAGER_SHUTDOWN);
 }
 
 void PrerenderManager::SetPrerenderContentsFactory(
@@ -1001,6 +996,16 @@ Value* PrerenderManager::GetAsValue() const {
   return dict_value;
 }
 
+void PrerenderManager::ClearData(int clear_flags) {
+  DCHECK_GE(clear_flags, 0);
+  DCHECK_LT(clear_flags, CLEAR_MAX);
+  if (clear_flags & CLEAR_PRERENDER_CONTENTS)
+    DestroyAllContents(FINAL_STATUS_CACHE_OR_HISTORY_CLEARED);
+  // This has to be second, since destroying prerenders can add to the history.
+  if (clear_flags & CLEAR_PRERENDER_HISTORY)
+    prerender_history_->Clear();
+}
+
 Value* PrerenderManager::GetActivePrerendersAsValue() const {
   ListValue* list_value = new ListValue();
   for (std::list<PrerenderContentsData>::const_iterator it =
@@ -1021,4 +1026,14 @@ void PrerenderManager::AddToHistory(PrerenderContents* contents) {
   prerender_history_->AddEntry(entry);
 }
 
+void PrerenderManager::DestroyAllContents(FinalStatus final_status) {
+  DeleteOldTabContents();
+  while (!prerender_list_.empty()) {
+    PrerenderContentsData data = prerender_list_.front();
+    prerender_list_.pop_front();
+    data.contents_->Destroy(final_status);
+  }
+  DeletePendingDeleteEntries();
+}
+
 }  // namespace prerender
diff --git a/chrome/browser/prerender/prerender_manager.h b/chrome/browser/prerender/prerender_manager.h
index 65547d0..96e3090 100644
--- a/chrome/browser/prerender/prerender_manager.h
+++ b/chrome/browser/prerender/prerender_manager.h
@@ -73,6 +73,14 @@ class PrerenderManager : public base::SupportsWeakPtr<PrerenderManager>,
     PRERENDER_MODE_MAX
   };
 
+  // One or more of these flags must be passed to ClearData() to specify just
+  // what data to clear.  See function declaration for more information.
+  enum ClearFlags {
+    CLEAR_PRERENDER_CONTENTS = 0x1 << 0,
+    CLEAR_PRERENDER_HISTORY = 0x1 << 1,
+    CLEAR_MAX = 0x1 << 2
+  };
+
   // Owned by a Profile object for the lifetime of the profile.
   PrerenderManager(Profile* profile, PrerenderTracker* prerender_tracker);
 
@@ -195,11 +203,25 @@ class PrerenderManager : public base::SupportsWeakPtr<PrerenderManager>,
   // deleting the return value.
   Value* GetAsValue() const;
 
+  // Clears the data indicated by which bits of clear_flags are set.
+  //
+  // If the CLEAR_PRERENDER_CONTENTS bit is set, all active prerenders are
+  // cancelled and then deleted, and any TabContents queued for destruction are
+  // destroyed as well.
+  //
+  // If the CLEAR_PRERENDER_HISTORY bit is set, the prerender history is
+  // cleared, including any entries newly created by destroying them in
+  // response to the CLEAR_PRERENDER_CONTENTS flag.
+  //
+  // Intended to be used when clearing the cache or history.
+  void ClearData(int clear_flags);
+
  protected:
   struct PendingContentsData;
 
   void SetPrerenderContentsFactory(
       PrerenderContents::Factory* prerender_contents_factory);
+
   bool rate_limit_enabled_;
 
   PendingContentsData* FindPendingEntry(const GURL& url);
@@ -292,6 +314,11 @@ class PrerenderManager : public base::SupportsWeakPtr<PrerenderManager>,
   // caller is responsible for delete'ing the return value.
   Value* GetActivePrerendersAsValue() const;
 
+  // Destroys all pending prerenders using FinalStatus.  Also deletes them as
+  // well as any swapped out TabContents queued for destruction.
+  // Used both on destruction, and when clearing the browing history.
+  void DestroyAllContents(FinalStatus final_status);
+
   // Specifies whether prerendering is currently enabled for this
   // manager. The value can change dynamically during the lifetime
   // of the PrerenderManager.
diff --git a/chrome/browser/prerender/prerender_manager_unittest.cc b/chrome/browser/prerender/prerender_manager_unittest.cc
index 9b82c16..63b2a63 100644
--- a/chrome/browser/prerender/prerender_manager_unittest.cc
+++ b/chrome/browser/prerender/prerender_manager_unittest.cc
@@ -519,4 +519,18 @@ TEST_F(PrerenderManagerTest, FragmentMatchesFragmentTest) {
             prerender_manager()->GetEntry(other_fragment_url));
 }
 
+// Make sure that clearing works as expected.
+TEST_F(PrerenderManagerTest, ClearTest) {
+  GURL url("http://www.google.com/");
+  DummyPrerenderContents* prerender_contents =
+      prerender_manager()->CreateNextPrerenderContents(
+          url,
+          FINAL_STATUS_CACHE_OR_HISTORY_CLEARED);
+  EXPECT_TRUE(prerender_manager()->AddSimplePreload(url));
+  EXPECT_TRUE(prerender_contents->has_started());
+  prerender_manager()->ClearData(PrerenderManager::CLEAR_PRERENDER_CONTENTS);
+  DummyPrerenderContents* null = NULL;
+  EXPECT_EQ(null, prerender_manager()->GetEntry(url));
+}
+
 }  // namespace prerender