Re-land r56742 now with correct database files

A new field to describe the sources of history urls(visits) is added. This field is recorded in visit_database.
So far, it can tell imported, synchronized, entension added or other(mainly testing) entries from user browsed entries.
In the future, history extension API may allow queries to combinate with this criterion. 

BUG=none
TEST=Unit tests are already included. Please test the web browser with history from previous 
versions to make sure the migration could be done properly. Also try to import or sync some history and inspect the
sources added to the visit_source table in hitory database are correct.

Original review: http://codereview.chromium.org/2906004/show
Patch by weili@google.com

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@56971 0039d316-1c4b-4281-b951-d872f2087c98

19 files changed, 580 insertions, 93 deletions

diff --git a/chrome/browser/history/archived_database.cc b/chrome/browser/history/archived_database.cc
index 777ee4d..72fa998 100644
--- a/chrome/browser/history/archived_database.cc
+++ b/chrome/browser/history/archived_database.cc
@@ -13,7 +13,7 @@ namespace history {
 
 namespace {
 
-static const int kCurrentVersionNumber = 2;
+static const int kCurrentVersionNumber = 3;
 static const int kCompatibleVersionNumber = 2;
 
 }  // namespace
@@ -110,6 +110,12 @@ sql::InitStatus ArchivedDatabase::EnsureCurrentVersion() {
         std::min(cur_version, kCompatibleVersionNumber));
   }
 
+  if (cur_version == 2) {
+    // This is the version prior to adding visit_source table.
+    ++cur_version;
+    meta_table_.SetVersionNumber(cur_version);
+  }
+
   // Put future migration cases here.
 
   // When the version is too old, we just try to continue anyway, there should
diff --git a/chrome/browser/history/expire_history_backend.cc b/chrome/browser/history/expire_history_backend.cc
index bd471ad..294c0e6 100644
--- a/chrome/browser/history/expire_history_backend.cc
+++ b/chrome/browser/history/expire_history_backend.cc
@@ -512,7 +512,7 @@ void ExpireHistoryBackend::ExpireURLsForVisits(
 void ExpireHistoryBackend::ArchiveURLsAndVisits(
     const VisitVector& visits,
     DeleteDependencies* dependencies) {
-  if (!archived_db_)
+  if (!archived_db_ || !main_db_)
     return;
 
   // Make sure all unique URL rows are added to the dependency list and the
@@ -539,6 +539,12 @@ void ExpireHistoryBackend::ArchiveURLsAndVisits(
     }
   }
 
+  // Retrieve the sources for all the archived visits before archiving.
+  // The returned visit_sources vector should contain the source for each visit
+  // from visits at the same index.
+  VisitSourceMap visit_sources;
+  main_db_->GetVisitsSource(visits, &visit_sources);
+
   // Now archive the visits since we know the URL ID to make them reference.
   // The source visit list should still reference the visits in the main DB, but
   // we will update it to reflect only the visits that were successfully
@@ -550,7 +556,9 @@ void ExpireHistoryBackend::ArchiveURLsAndVisits(
     VisitRow cur_visit(visits[i]);
     cur_visit.url_id = main_id_to_archived_id[cur_visit.url_id];
     cur_visit.referring_visit = 0;
-    archived_db_->AddVisit(&cur_visit);
+    VisitSourceMap::iterator iter = visit_sources.find(visits[i].visit_id);
+    archived_db_->AddVisit(&cur_visit,
+        iter == visit_sources.end() ? SOURCE_BROWSED : iter->second);
     // Ignore failures, we will delete it from the main DB no matter what.
   }
 }
diff --git a/chrome/browser/history/expire_history_backend.h b/chrome/browser/history/expire_history_backend.h
index 4bd18b0..96e2e9a 100644
--- a/chrome/browser/history/expire_history_backend.h
+++ b/chrome/browser/history/expire_history_backend.h
@@ -106,6 +106,7 @@ class ExpireHistoryBackend {
   FRIEND_TEST_ALL_PREFIXES(ExpireHistoryTest, DeleteFaviconsIfPossible);
   FRIEND_TEST_ALL_PREFIXES(ExpireHistoryTest, ArchiveSomeOldHistory);
   FRIEND_TEST_ALL_PREFIXES(ExpireHistoryTest, ExpiringVisitsReader);
+  FRIEND_TEST_ALL_PREFIXES(ExpireHistoryTest, ArchiveSomeOldHistoryWithSource);
   friend class ::TestingProfile;
 
   struct DeleteDependencies;
diff --git a/chrome/browser/history/expire_history_backend_unittest.cc b/chrome/browser/history/expire_history_backend_unittest.cc
index 60c783d..ef65eab 100644
--- a/chrome/browser/history/expire_history_backend_unittest.cc
+++ b/chrome/browser/history/expire_history_backend_unittest.cc
@@ -56,6 +56,8 @@ class ExpireHistoryTest : public testing::Test,
  protected:
   // Called by individual tests when they want data populated.
   void AddExampleData(URLID url_ids[3], Time visit_times[4]);
+  // Add visits with source information.
+  void AddExampleSourceData(const GURL& url, URLID* id);
 
   // Returns true if the given favicon/thumanil has an entry in the DB.
   bool HasFavIcon(FavIconID favicon_id);
@@ -227,26 +229,26 @@ void ExpireHistoryTest::AddExampleData(URLID url_ids[3], Time visit_times[4]) {
   visit_row1.url_id = url_ids[0];
   visit_row1.visit_time = visit_times[0];
   visit_row1.is_indexed = true;
-  main_db_->AddVisit(&visit_row1);
+  main_db_->AddVisit(&visit_row1, SOURCE_BROWSED);
 
   VisitRow visit_row2;
   visit_row2.url_id = url_ids[1];
   visit_row2.visit_time = visit_times[1];
   visit_row2.is_indexed = true;
-  main_db_->AddVisit(&visit_row2);
+  main_db_->AddVisit(&visit_row2, SOURCE_BROWSED);
 
   VisitRow visit_row3;
   visit_row3.url_id = url_ids[1];
   visit_row3.visit_time = visit_times[2];
   visit_row3.is_indexed = true;
   visit_row3.transition = PageTransition::TYPED;
-  main_db_->AddVisit(&visit_row3);
+  main_db_->AddVisit(&visit_row3, SOURCE_BROWSED);
 
   VisitRow visit_row4;
   visit_row4.url_id = url_ids[2];
   visit_row4.visit_time = visit_times[3];
   visit_row4.is_indexed = true;
-  main_db_->AddVisit(&visit_row4);
+  main_db_->AddVisit(&visit_row4, SOURCE_BROWSED);
 
   // Full text index for each visit.
   text_db_->AddPageData(url_row1.url(), visit_row1.url_id, visit_row1.visit_id,
@@ -267,6 +269,35 @@ void ExpireHistoryTest::AddExampleData(URLID url_ids[3], Time visit_times[4]) {
                         UTF8ToUTF16("goats body"));
 }
 
+void ExpireHistoryTest::AddExampleSourceData(const GURL& url, URLID* id) {
+  if (!main_db_.get())
+    return;
+
+  Time last_visit_time = Time::Now();
+  // Add one URL.
+  URLRow url_row1(url);
+  url_row1.set_last_visit(last_visit_time);
+  url_row1.set_visit_count(4);
+  URLID url_id = main_db_->AddURL(url_row1);
+  *id = url_id;
+
+  // Four times for each visit.
+  VisitRow visit_row1(url_id, last_visit_time - TimeDelta::FromDays(4), 0,
+                      PageTransition::TYPED, 0);
+  main_db_->AddVisit(&visit_row1, SOURCE_SYNCED);
+
+  VisitRow visit_row2(url_id, last_visit_time - TimeDelta::FromDays(3), 0,
+                      PageTransition::TYPED, 0);
+  main_db_->AddVisit(&visit_row2, SOURCE_BROWSED);
+
+  VisitRow visit_row3(url_id, last_visit_time - TimeDelta::FromDays(2), 0,
+                      PageTransition::TYPED, 0);
+  main_db_->AddVisit(&visit_row3, SOURCE_EXTENSION);
+
+  VisitRow visit_row4(url_id, last_visit_time, 0, PageTransition::TYPED, 0);
+  main_db_->AddVisit(&visit_row4, SOURCE_FIREFOX_IMPORTED);
+}
+
 bool ExpireHistoryTest::HasFavIcon(FavIconID favicon_id) {
   if (!thumb_db_.get())
     return false;
@@ -815,6 +846,50 @@ TEST_F(ExpireHistoryTest, ExpiringVisitsReader) {
   EXPECT_EQ(1U, visits.size());
 }
 
+// Tests how ArchiveSomeOldHistory treats source information.
+TEST_F(ExpireHistoryTest, ArchiveSomeOldHistoryWithSource) {
+  const GURL url("www.testsource.com");
+  URLID url_id;
+  AddExampleSourceData(url, &url_id);
+  const ExpiringVisitsReader* reader = expirer_.GetAllVisitsReader();
+
+  // Archiving all the visits we added.
+  ASSERT_FALSE(expirer_.ArchiveSomeOldHistory(Time::Now(), reader, 10));
+
+  URLRow archived_row;
+  ASSERT_TRUE(archived_db_->GetRowForURL(url, &archived_row));
+  VisitVector archived_visits;
+  archived_db_->GetVisitsForURL(archived_row.id(), &archived_visits);
+  ASSERT_EQ(4U, archived_visits.size());
+  VisitSourceMap sources;
+  archived_db_->GetVisitsSource(archived_visits, &sources);
+  ASSERT_EQ(3U, sources.size());
+  int result = 0;
+  VisitSourceMap::iterator iter;
+  for (int i = 0; i < 4; i++) {
+    iter = sources.find(archived_visits[i].visit_id);
+    if (iter == sources.end())
+      continue;
+    switch (iter->second) {
+      case history::SOURCE_EXTENSION:
+        result |= 0x1;
+        break;
+      case history::SOURCE_FIREFOX_IMPORTED:
+        result |= 0x2;
+        break;
+      case history::SOURCE_SYNCED:
+        result |= 0x4;
+      default:
+        break;
+    }
+  }
+  EXPECT_EQ(0x7, result);
+  main_db_->GetVisitsSource(archived_visits, &sources);
+  EXPECT_EQ(0U, sources.size());
+  main_db_->GetVisitsForURL(url_id, &archived_visits);
+  EXPECT_EQ(0U, archived_visits.size());
+}
+
 // TODO(brettw) add some visits with no URL to make sure everything is updated
 // properly. Have the visits also refer to nonexistant FTS rows.
 //
diff --git a/chrome/browser/history/history.cc b/chrome/browser/history/history.cc
index 156f9da..eb27b97 100644
--- a/chrome/browser/history/history.cc
+++ b/chrome/browser/history/history.cc
@@ -301,9 +301,10 @@ void HistoryService::AddPage(const GURL& url,
                              const GURL& referrer,
                              PageTransition::Type transition,
                              const history::RedirectList& redirects,
+                             history::VisitSource visit_source,
                              bool did_replace_entry) {
   AddPage(url, Time::Now(), id_scope, page_id, referrer, transition, redirects,
-          did_replace_entry);
+          visit_source, did_replace_entry);
 }
 
 void HistoryService::AddPage(const GURL& url,
@@ -313,6 +314,7 @@ void HistoryService::AddPage(const GURL& url,
                              const GURL& referrer,
                              PageTransition::Type transition,
                              const history::RedirectList& redirects,
+                             history::VisitSource visit_source,
                              bool did_replace_entry) {
   DCHECK(thread_) << "History service being called after cleanup";
 
@@ -340,8 +342,8 @@ void HistoryService::AddPage(const GURL& url,
   }
 
   scoped_refptr<history::HistoryAddPageArgs> request(
-      new history::HistoryAddPageArgs(url, time, id_scope, page_id,
-                                      referrer, redirects, transition,
+      new history::HistoryAddPageArgs(url, time, id_scope, page_id, referrer,
+                                      redirects, transition, visit_source,
                                       did_replace_entry));
   ScheduleAndForget(PRIORITY_NORMAL, &HistoryBackend::AddPage, request);
 }
@@ -356,7 +358,8 @@ void HistoryService::AddPageWithDetails(const GURL& url,
                                         int visit_count,
                                         int typed_count,
                                         Time last_visit,
-                                        bool hidden) {
+                                        bool hidden,
+                                        history::VisitSource visit_source) {
   // Filter out unwanted URLs.
   if (!CanAddURL(url))
     return;
@@ -377,11 +380,12 @@ void HistoryService::AddPageWithDetails(const GURL& url,
   rows.push_back(row);
 
   ScheduleAndForget(PRIORITY_NORMAL,
-                    &HistoryBackend::AddPagesWithDetails, rows);
+                    &HistoryBackend::AddPagesWithDetails, rows, visit_source);
 }
 
 void HistoryService::AddPagesWithDetails(
-    const std::vector<history::URLRow>& info) {
+    const std::vector<history::URLRow>& info,
+    history::VisitSource visit_source) {
 
   // Add to the visited links system.
   VisitedLinkMaster* visited_links;
@@ -397,7 +401,7 @@ void HistoryService::AddPagesWithDetails(
   }
 
   ScheduleAndForget(PRIORITY_NORMAL,
-                    &HistoryBackend::AddPagesWithDetails, info);
+                    &HistoryBackend::AddPagesWithDetails, info, visit_source);
 }
 
 void HistoryService::SetPageContents(const GURL& url,
diff --git a/chrome/browser/history/history.h b/chrome/browser/history/history.h
index c142c97..5bc3b7f 100644
--- a/chrome/browser/history/history.h
+++ b/chrome/browser/history/history.h
@@ -185,6 +185,7 @@ class HistoryService : public CancelableRequestProvider,
                const GURL& referrer,
                PageTransition::Type transition,
                const history::RedirectList& redirects,
+               history::VisitSource visit_source,
                bool did_replace_entry);
 
   // For adding pages to history with a specific time. This is for testing
@@ -196,12 +197,13 @@ class HistoryService : public CancelableRequestProvider,
                const GURL& referrer,
                PageTransition::Type transition,
                const history::RedirectList& redirects,
+               history::VisitSource visit_source,
                bool did_replace_entry);
 
   // For adding pages to history where no tracking information can be done.
-  void AddPage(const GURL& url) {
-    AddPage(url, NULL, 0, GURL(), PageTransition::LINK, history::RedirectList(),
-            false);
+  void AddPage(const GURL& url, history::VisitSource visit_source) {
+    AddPage(url, NULL, 0, GURL(), PageTransition::LINK,
+            history::RedirectList(), visit_source, false);
   }
 
   // Sets the title for the given page. The page should be in history. If it
@@ -535,10 +537,12 @@ class HistoryService : public CancelableRequestProvider,
                           int visit_count,
                           int typed_count,
                           base::Time last_visit,
-                          bool hidden);
+                          bool hidden,
+                          history::VisitSource visit_source);
 
   // The same as AddPageWithDetails() but takes a vector.
-  void AddPagesWithDetails(const std::vector<history::URLRow>& info);
+  void AddPagesWithDetails(const std::vector<history::URLRow>& info,
+                           history::VisitSource visit_source);
 
   // Starts the TopSites migration in the HistoryThread. Called by the
   // BackendDelegate.
diff --git a/chrome/browser/history/history_backend.cc b/chrome/browser/history/history_backend.cc
index 91aba75..847dc6e 100644
--- a/chrome/browser/history/history_backend.cc
+++ b/chrome/browser/history/history_backend.cc
@@ -405,7 +405,7 @@ void HistoryBackend::AddPage(scoped_refptr<HistoryAddPageArgs> request) {
 
     // No redirect case (one element means just the page itself).
     last_ids = AddPageVisit(request->url, last_recorded_time_,
-                            last_ids.second, t);
+                            last_ids.second, t, request->visit_source);
 
     // Update the segment for this visit. KEYWORD_GENERATED visits should not
     // result in changing most visited, so we don't update segments (most
@@ -471,7 +471,8 @@ void HistoryBackend::AddPage(scoped_refptr<HistoryAddPageArgs> request) {
       // them anyway, and if we ever decide to, we can reconstruct their order
       // from the redirect chain.
       last_ids = AddPageVisit(request->redirects[redirect_index],
-                              last_recorded_time_, last_ids.second, t);
+                              last_recorded_time_, last_ids.second,
+                              t, request->visit_source);
       if (t & PageTransition::CHAIN_START) {
         // Update the segment for this visit.
         UpdateSegments(request->redirects[redirect_index],
@@ -651,7 +652,8 @@ std::pair<URLID, VisitID> HistoryBackend::AddPageVisit(
     const GURL& url,
     Time time,
     VisitID referring_visit,
-    PageTransition::Type transition) {
+    PageTransition::Type transition,
+    VisitSource visit_source) {
   // Top-level frame navigations are visible, everything else is hidden
   bool new_hidden = !PageTransition::IsMainFrame(transition);
 
@@ -708,7 +710,7 @@ std::pair<URLID, VisitID> HistoryBackend::AddPageVisit(
 
   // Add the visit with the time to the database.
   VisitRow visit_info(url_id, time, referring_visit, transition, 0);
-  VisitID visit_id = db_->AddVisit(&visit_info);
+  VisitID visit_id = db_->AddVisit(&visit_info, visit_source);
 
   if (visit_info.visit_time < first_recorded_time_)
     first_recorded_time_ = visit_info.visit_time;
@@ -727,7 +729,8 @@ std::pair<URLID, VisitID> HistoryBackend::AddPageVisit(
   return std::make_pair(url_id, visit_id);
 }
 
-void HistoryBackend::AddPagesWithDetails(const std::vector<URLRow>& urls) {
+void HistoryBackend::AddPagesWithDetails(const std::vector<URLRow>& urls,
+                                         VisitSource visit_source) {
   if (!db_.get())
     return;
 
@@ -789,7 +792,7 @@ void HistoryBackend::AddPagesWithDetails(const std::vector<URLRow>& urls) {
         PageTransition::LINK | PageTransition::CHAIN_START |
         PageTransition::CHAIN_END, 0);
     visit_info.is_indexed = has_indexed;
-    if (!visit_database->AddVisit(&visit_info)) {
+    if (!visit_database->AddVisit(&visit_info, visit_source)) {
       NOTREACHED() << "Adding visit failed.";
       return;
     }
@@ -906,11 +909,12 @@ bool HistoryBackend::UpdateURL(URLID id, const history::URLRow& url) {
 }
 
 bool HistoryBackend::AddVisits(const GURL& url,
-                               const std::vector<base::Time>& visits) {
+                               const std::vector<base::Time>& visits,
+                               VisitSource visit_source) {
   if (db_.get()) {
     for (std::vector<base::Time>::const_iterator visit = visits.begin();
          visit != visits.end(); ++visit) {
-      if (!AddPageVisit(url, *visit, 0, 0).first) {
+      if (!AddPageVisit(url, *visit, 0, 0, visit_source).first) {
         return false;
       }
     }
diff --git a/chrome/browser/history/history_backend.h b/chrome/browser/history/history_backend.h
index 4d333f3..1965bc5 100644
--- a/chrome/browser/history/history_backend.h
+++ b/chrome/browser/history/history_backend.h
@@ -258,8 +258,10 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
 
   virtual bool UpdateURL(URLID id, const history::URLRow& url);
 
+  // While adding visits in batch, the source needs to be provided.
   virtual bool AddVisits(const GURL& url,
-                         const std::vector<base::Time>& visits);
+                         const std::vector<base::Time>& visits,
+                         VisitSource visit_source);
 
   virtual bool RemoveVisits(const VisitVector& visits);
 
@@ -292,7 +294,9 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
 
   // Adds the given rows to the database if it doesn't exist. A visit will be
   // added for each given URL at the last visit time in the URLRow.
-  void AddPagesWithDetails(const std::vector<URLRow>& info);
+  // Each visit will have the visit_source type set.
+  void AddPagesWithDetails(const std::vector<URLRow>& info,
+                           VisitSource visit_source);
 
 #if defined(UNIT_TEST)
   HistoryDatabase* db() const { return db_.get(); }
@@ -312,6 +316,11 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, URLsNoLongerBookmarked);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, StripUsernamePasswordTest);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, DeleteThumbnailsDatabaseTest);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddPageVisitSource);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddPageArgsSource);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddVisitsSource);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, RemoveVisitsSource);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, MigrationVisitSource);
   friend class ::TestingProfile;
 
   // Computes the name of the specified database on disk.
@@ -339,7 +348,8 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
   std::pair<URLID, VisitID> AddPageVisit(const GURL& url,
                                          base::Time time,
                                          VisitID referring_visit,
-                                         PageTransition::Type transition);
+                                         PageTransition::Type transition,
+                                         VisitSource visit_source);
 
   // Returns a redirect chain in |redirects| for the VisitID
   // |cur_visit|. |cur_visit| is assumed to be valid. Assumes that
diff --git a/chrome/browser/history/history_backend_unittest.cc b/chrome/browser/history/history_backend_unittest.cc
index ff91c53..68fd2e2 100644
--- a/chrome/browser/history/history_backend_unittest.cc
+++ b/chrome/browser/history/history_backend_unittest.cc
@@ -15,6 +15,8 @@
 #include "chrome/browser/history/history_notifications.h"
 #include "chrome/browser/history/in_memory_history_backend.h"
 #include "chrome/browser/history/in_memory_database.h"
+#include "chrome/common/chrome_constants.h"
+#include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/notification_service.h"
 #include "chrome/common/thumbnail_score.h"
@@ -75,7 +77,7 @@ class HistoryBackendTest : public testing::Test {
     scoped_refptr<history::HistoryAddPageArgs> request(
         new history::HistoryAddPageArgs(
             redirects.back(), Time::Now(), scope, page_id, GURL(),
-            redirects, PageTransition::LINK, true));
+            redirects, PageTransition::LINK, history::SOURCE_BROWSED, true));
     backend_->AddPage(request);
   }
 
@@ -95,7 +97,8 @@ class HistoryBackendTest : public testing::Test {
       redirects.push_back(url2);
     scoped_refptr<HistoryAddPageArgs> request(
         new HistoryAddPageArgs(url2, base::Time(), dummy_scope, 0, url1,
-            redirects, PageTransition::CLIENT_REDIRECT, did_replace));
+            redirects, PageTransition::CLIENT_REDIRECT,
+            history::SOURCE_BROWSED, did_replace));
     backend_->AddPage(request);
 
     *transition1 = getTransition(url1);
@@ -112,6 +115,10 @@ class HistoryBackendTest : public testing::Test {
     return visits[0].transition;
   }
 
+  FilePath getTestDir() {
+    return test_dir_;
+  }
+
   BookmarkModel bookmark_model_;
 
  protected:
@@ -215,7 +222,7 @@ TEST_F(HistoryBackendTest, DeleteAll) {
   std::vector<URLRow> rows;
   rows.push_back(row2);  // Reversed order for the same reason as favicons.
   rows.push_back(row1);
-  backend_->AddPagesWithDetails(rows);
+  backend_->AddPagesWithDetails(rows, history::SOURCE_BROWSED);
 
   URLID row1_id = backend_->db_->GetRowForURL(row1.url(), NULL);
   URLID row2_id = backend_->db_->GetRowForURL(row2.url(), NULL);
@@ -345,7 +352,7 @@ TEST_F(HistoryBackendTest, URLsNoLongerBookmarked) {
   std::vector<URLRow> rows;
   rows.push_back(row2);  // Reversed order for the same reason as favicons.
   rows.push_back(row1);
-  backend_->AddPagesWithDetails(rows);
+  backend_->AddPagesWithDetails(rows, history::SOURCE_BROWSED);
 
   URLID row1_id = backend_->db_->GetRowForURL(row1.url(), NULL);
   URLID row2_id = backend_->db_->GetRowForURL(row2.url(), NULL);
@@ -454,7 +461,8 @@ TEST_F(HistoryBackendTest, KeywordGenerated) {
   scoped_refptr<HistoryAddPageArgs> request(
       new HistoryAddPageArgs(url, visit_time, NULL, 0, GURL(),
                              history::RedirectList(),
-                             PageTransition::KEYWORD_GENERATED, false));
+                             PageTransition::KEYWORD_GENERATED,
+                             history::SOURCE_BROWSED, false));
   backend_->AddPage(request);
 
   // A row should have been added for the url.
@@ -537,7 +545,7 @@ TEST_F(HistoryBackendTest, ImportedFaviconsTest) {
   std::vector<URLRow> rows;
   rows.push_back(row1);
   rows.push_back(row2);
-  backend_->AddPagesWithDetails(rows);
+  backend_->AddPagesWithDetails(rows, history::SOURCE_BROWSED);
   URLRow url_row1, url_row2;
   EXPECT_FALSE(backend_->db_->GetRowForURL(row1.url(), &url_row1) == 0);
   EXPECT_FALSE(backend_->db_->GetRowForURL(row2.url(), &url_row2) == 0);
@@ -592,7 +600,8 @@ TEST_F(HistoryBackendTest, StripUsernamePasswordTest) {
 
   // Visit the url with username, password.
   backend_->AddPageVisit(url, base::Time::Now(), 0,
-    PageTransition::GetQualifier(PageTransition::TYPED));
+    PageTransition::GetQualifier(PageTransition::TYPED),
+    history::SOURCE_BROWSED);
 
   // Fetch the row information about stripped url from history db.
   VisitVector visits;
@@ -612,4 +621,214 @@ TEST_F(HistoryBackendTest, DeleteThumbnailsDatabaseTest) {
   EXPECT_FALSE(backend_->thumbnail_db_->NeedsMigrationToTopSites());
 }
 
+TEST_F(HistoryBackendTest, AddPageVisitSource) {
+  ASSERT_TRUE(backend_.get());
+
+  GURL url("http://www.google.com");
+
+  // Clear all history.
+  backend_->DeleteAllHistory();
+
+  // Assume visiting the url from an externsion.
+  backend_->AddPageVisit(url, base::Time::Now(), 0, PageTransition::TYPED,
+                         history::SOURCE_EXTENSION);
+  // Assume the url is imported from Firefox.
+  backend_->AddPageVisit(url, base::Time::Now(), 0, PageTransition::TYPED,
+                         history::SOURCE_FIREFOX_IMPORTED);
+  // Assume this url is also synced.
+  backend_->AddPageVisit(url, base::Time::Now(), 0, PageTransition::TYPED,
+                         history::SOURCE_SYNCED);
+
+  // Fetch the row information about the url from history db.
+  VisitVector visits;
+  URLID row_id = backend_->db_->GetRowForURL(url, NULL);
+  backend_->db_->GetVisitsForURL(row_id, &visits);
+
+  // Check if all the visits to the url are stored in database.
+  ASSERT_EQ(3U, visits.size());
+  VisitSourceMap visit_sources;
+  backend_->db_->GetVisitsSource(visits, &visit_sources);
+  ASSERT_EQ(3U, visit_sources.size());
+  int sources = 0;
+  for (int i = 0; i < 3; i++) {
+    switch (visit_sources[visits[i].visit_id]) {
+      case history::SOURCE_EXTENSION:
+        sources |= 0x1;
+        break;
+      case history::SOURCE_FIREFOX_IMPORTED:
+        sources |= 0x2;
+        break;
+      case history::SOURCE_SYNCED:
+        sources |= 0x4;
+      default:
+        break;
+    }
+  }
+  EXPECT_EQ(0x7, sources);
+}
+
+TEST_F(HistoryBackendTest, AddPageArgsSource) {
+  ASSERT_TRUE(backend_.get());
+
+  GURL url("http://testpageargs.com");
+
+  // Assume this page is browsed by user.
+  scoped_refptr<HistoryAddPageArgs> request1(
+      new HistoryAddPageArgs(url, base::Time::Now(), NULL, 0, GURL(),
+                             history::RedirectList(),
+                             PageTransition::KEYWORD_GENERATED,
+                             history::SOURCE_BROWSED, false));
+  backend_->AddPage(request1);
+  // Assume this page is synced.
+  scoped_refptr<HistoryAddPageArgs> request2(
+      new HistoryAddPageArgs(url, base::Time::Now(), NULL, 0, GURL(),
+                             history::RedirectList(),
+                             PageTransition::LINK,
+                             history::SOURCE_SYNCED, false));
+  backend_->AddPage(request2);
+  // Assume this page is browsed again.
+  scoped_refptr<HistoryAddPageArgs> request3(
+      new HistoryAddPageArgs(url, base::Time::Now(), NULL, 0, GURL(),
+                             history::RedirectList(),
+                             PageTransition::TYPED,
+                             history::SOURCE_BROWSED, false));
+  backend_->AddPage(request3);
+
+  // Three visits should be added with proper sources.
+  VisitVector visits;
+  URLRow row;
+  URLID id = backend_->db()->GetRowForURL(url, &row);
+  ASSERT_TRUE(backend_->db()->GetVisitsForURL(id, &visits));
+  ASSERT_EQ(3U, visits.size());
+  VisitSourceMap visit_sources;
+  backend_->db_->GetVisitsSource(visits, &visit_sources);
+  ASSERT_EQ(1U, visit_sources.size());
+  EXPECT_EQ(history::SOURCE_SYNCED, visit_sources.begin()->second);
+}
+
+TEST_F(HistoryBackendTest, AddVisitsSource) {
+  ASSERT_TRUE(backend_.get());
+
+  GURL url1("http://www.cnn.com");
+  std::vector<base::Time> visits1;
+  visits1.push_back(Time::Now() - base::TimeDelta::FromDays(5));
+  visits1.push_back(Time::Now() - base::TimeDelta::FromDays(1));
+  visits1.push_back(Time::Now());
+
+  GURL url2("http://www.example.com");
+  std::vector<base::Time> visits2;
+  visits2.push_back(Time::Now() - base::TimeDelta::FromDays(10));
+  visits2.push_back(Time::Now());
+
+  // Clear all history.
+  backend_->DeleteAllHistory();
+
+  // Add the visits.
+  backend_->AddVisits(url1, visits1, history::SOURCE_IE_IMPORTED);
+  backend_->AddVisits(url2, visits2, history::SOURCE_SYNCED);
+
+  // Verify the visits were added with their sources.
+  VisitVector visits;
+  URLRow row;
+  URLID id = backend_->db()->GetRowForURL(url1, &row);
+  ASSERT_TRUE(backend_->db()->GetVisitsForURL(id, &visits));
+  ASSERT_EQ(3U, visits.size());
+  VisitSourceMap visit_sources;
+  backend_->db_->GetVisitsSource(visits, &visit_sources);
+  ASSERT_EQ(3U, visit_sources.size());
+  for (int i = 0; i < 3; i++)
+    EXPECT_EQ(history::SOURCE_IE_IMPORTED, visit_sources[visits[i].visit_id]);
+  id = backend_->db()->GetRowForURL(url2, &row);
+  ASSERT_TRUE(backend_->db()->GetVisitsForURL(id, &visits));
+  ASSERT_EQ(2U, visits.size());
+  backend_->db_->GetVisitsSource(visits, &visit_sources);
+  ASSERT_EQ(2U, visit_sources.size());
+  for (int i = 0; i < 2; i++)
+    EXPECT_EQ(history::SOURCE_SYNCED, visit_sources[visits[i].visit_id]);
+}
+
+TEST_F(HistoryBackendTest, RemoveVisitsSource) {
+  ASSERT_TRUE(backend_.get());
+
+  GURL url1("http://www.cnn.com");
+  std::vector<base::Time> visits1;
+  visits1.push_back(Time::Now() - base::TimeDelta::FromDays(5));
+  visits1.push_back(Time::Now());
+
+  GURL url2("http://www.example.com");
+  std::vector<base::Time> visits2;
+  visits2.push_back(Time::Now() - base::TimeDelta::FromDays(10));
+  visits2.push_back(Time::Now());
+
+  // Clear all history.
+  backend_->DeleteAllHistory();
+
+  // Add the visits.
+  backend_->AddVisits(url1, visits1, history::SOURCE_IE_IMPORTED);
+  backend_->AddVisits(url2, visits2, history::SOURCE_SYNCED);
+
+  // Verify the visits of url1 were added.
+  VisitVector visits;
+  URLRow row;
+  URLID id = backend_->db()->GetRowForURL(url1, &row);
+  ASSERT_TRUE(backend_->db()->GetVisitsForURL(id, &visits));
+  ASSERT_EQ(2U, visits.size());
+  // Remove these visits.
+  ASSERT_TRUE(backend_->RemoveVisits(visits));
+
+  // Now check only url2's source in visit_source table.
+  VisitSourceMap visit_sources;
+  backend_->db_->GetVisitsSource(visits, &visit_sources);
+  ASSERT_EQ(0U, visit_sources.size());
+  id = backend_->db()->GetRowForURL(url2, &row);
+  ASSERT_TRUE(backend_->db()->GetVisitsForURL(id, &visits));
+  ASSERT_EQ(2U, visits.size());
+  backend_->db_->GetVisitsSource(visits, &visit_sources);
+  ASSERT_EQ(2U, visit_sources.size());
+  for (int i = 0; i < 2; i++)
+    EXPECT_EQ(history::SOURCE_SYNCED, visit_sources[visits[i].visit_id]);
+}
+
+// Test for migration of adding visit_source table.
+TEST_F(HistoryBackendTest, MigrationVisitSource) {
+  ASSERT_TRUE(backend_.get());
+
+  FilePath old_history_path;
+  ASSERT_TRUE(PathService::Get(chrome::DIR_TEST_DATA, &old_history_path));
+  old_history_path = old_history_path.AppendASCII("History");
+  old_history_path = old_history_path.AppendASCII("HistoryNoSource");
+
+  // Copy history database file to current directory so that it will be deleted
+  // in Teardown.
+  FilePath new_history_path(getTestDir());
+  file_util::Delete(new_history_path, true);
+  file_util::CreateDirectory(new_history_path);
+  FilePath new_history_file = new_history_path.Append(chrome::kHistoryFilename);
+  ASSERT_TRUE(file_util::CopyFile(old_history_path, new_history_file));
+
+  backend_->Closing();
+  backend_ = new HistoryBackend(new_history_path,
+                                new HistoryBackendTestDelegate(this),
+                                &bookmark_model_);
+  backend_->Init(false);
+
+  // Now the database should already be migrated.
+  // Check version first.
+  int cur_version = HistoryDatabase::GetCurrentVersion();
+  sql::Connection db;
+  ASSERT_TRUE(db.Open(new_history_file));
+  sql::Statement s(db.GetUniqueStatement(
+      "SELECT value FROM meta WHERE key = 'version'"));
+  ASSERT_TRUE(s.Step());
+  int file_version = s.ColumnInt(0);
+  EXPECT_EQ(cur_version, file_version);
+
+  // Check visit_source table is created and empty.
+  s.Assign(db.GetUniqueStatement(
+      "SELECT name FROM sqlite_master WHERE name=\"visit_source\""));
+  ASSERT_TRUE(s.Step());
+  s.Assign(db.GetUniqueStatement("SELECT * FROM visit_source LIMIT 10"));
+  EXPECT_FALSE(s.Step());
+}
+
 }  // namespace history
diff --git a/chrome/browser/history/history_database.cc b/chrome/browser/history/history_database.cc
index 7869fcc..4fab291 100644
--- a/chrome/browser/history/history_database.cc
+++ b/chrome/browser/history/history_database.cc
@@ -26,7 +26,7 @@ namespace {
 // Current version number. We write databases at the "current" version number,
 // but any previous version that can read the "compatible" one can make do with
 // or database without *too* many bad effects.
-static const int kCurrentVersionNumber = 18;
+static const int kCurrentVersionNumber = 19;
 static const int kCompatibleVersionNumber = 16;
 static const char kEarlyExpirationThresholdKey[] = "early_expiration_threshold";
 
@@ -134,7 +134,7 @@ void HistoryDatabase::BeginExclusiveMode() {
 
 // static
 int HistoryDatabase::GetCurrentVersion() {
-  // If we don't use TopSites, we are one version number behind.
+  // If we don't use TopSites, we stay at the last pre-TopSites version.
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kNoTopSites))
     return 17;  // Last pre-TopSites version.
   else
@@ -284,12 +284,19 @@ sql::InitStatus HistoryDatabase::EnsureCurrentVersion(
     needs_version_18_migration_ = true;
 
   if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kNoTopSites) &&
-      cur_version == 18) {
+      (cur_version == 18 || cur_version == 19)) {
     // Set DB version back to pre-top sites.
     cur_version = 17;
     meta_table_.SetVersionNumber(cur_version);
   }
 
+  if (needs_version_18_migration_ || cur_version == 18) {
+    // This is the version prior to adding url_source column. We need to
+    // migrate the database.
+    cur_version = 19;
+    meta_table_.SetVersionNumber(cur_version);
+  }
+
   // When the version is too old, we just try to continue anyway, there should
   // not be a released product that makes a database too old for us to handle.
   LOG_IF(WARNING, (cur_version < GetCurrentVersion() &&
@@ -325,9 +332,13 @@ void HistoryDatabase::MigrateTimeEpoch() {
 #endif
 
 void HistoryDatabase::MigrationToTopSitesDone() {
-  // We should be migrating from 17 to 18.
-  DCHECK_EQ(17, meta_table_.GetVersionNumber());
-  meta_table_.SetVersionNumber(18);
+  // Migration should only happen for version 17 and 19.
+  int version = meta_table_.GetVersionNumber();
+  DCHECK(17 == version || 19 == version);
+  if (17 == version) {
+    // We should be migrating from 17 to 18.
+    meta_table_.SetVersionNumber(18);
+  }
   needs_version_18_migration_ = false;
 }
 
diff --git a/chrome/browser/history/history_marshaling.h b/chrome/browser/history/history_marshaling.h
index 64cde29..e746d20 100644
--- a/chrome/browser/history/history_marshaling.h
+++ b/chrome/browser/history/history_marshaling.h
@@ -30,6 +30,7 @@ class HistoryAddPageArgs
                      const GURL& arg_referrer,
                      const history::RedirectList& arg_redirects,
                      PageTransition::Type arg_transition,
+                     VisitSource arg_source,
                      bool arg_did_replace_entry)
       : url(arg_url),
         time(arg_time),
@@ -38,6 +39,7 @@ class HistoryAddPageArgs
         referrer(arg_referrer),
         redirects(arg_redirects),
         transition(arg_transition),
+        visit_source(arg_source),
         did_replace_entry(arg_did_replace_entry) {
   }
 
@@ -50,6 +52,7 @@ class HistoryAddPageArgs
   GURL referrer;
   history::RedirectList redirects;
   PageTransition::Type transition;
+  VisitSource visit_source;
   bool did_replace_entry;
 
  private:
diff --git a/chrome/browser/history/history_querying_unittest.cc b/chrome/browser/history/history_querying_unittest.cc
index 7512786..7dbf5d1 100644
--- a/chrome/browser/history/history_querying_unittest.cc
+++ b/chrome/browser/history/history_querying_unittest.cc
@@ -111,7 +111,7 @@ class HistoryQueryTest : public testing::Test {
 
       history_->AddPage(url, test_entries[i].time, id_scope, page_id, GURL(),
                         PageTransition::LINK, history::RedirectList(),
-                        false);
+                        history::SOURCE_BROWSED, false);
       history_->SetPageTitle(url, UTF8ToUTF16(test_entries[i].title));
       history_->SetPageContents(url, UTF8ToUTF16(test_entries[i].body));
     }
@@ -314,7 +314,7 @@ TEST_F(HistoryQueryTest, FTSArchived) {
   row2.set_last_visit(Time::Now());
   urls_to_add.push_back(row2);
 
-  history_->AddPagesWithDetails(urls_to_add);
+  history_->AddPagesWithDetails(urls_to_add, history::SOURCE_BROWSED);
 
   QueryOptions options;
   QueryResults results;
diff --git a/chrome/browser/history/history_types.h b/chrome/browser/history/history_types.h
index 21e8067..de4b88c 100644
--- a/chrome/browser/history/history_types.h
+++ b/chrome/browser/history/history_types.h
@@ -176,9 +176,27 @@ class URLRow {
   // We support the implicit copy constuctor and operator=.
 };
 
-// VisitRow -------------------------------------------------------------------
+// The enumeration of all possible sources of visits is listed below.
+// The source will be propogated along with a URL or a visit item
+// and eventually be stored in the history database,
+// visit_source table specifically.
+// Different from page transition types, they describe the origins of visits.
+// (Warning): Please don't change any existing values while it is ok to add
+// new values when needed.
+typedef enum {
+  SOURCE_SYNCED = 0,         // Synchronized from somewhere else.
+  SOURCE_BROWSED = 1,        // User browsed.
+  SOURCE_EXTENSION = 2,      // Added by an externsion.
+  SOURCE_FIREFOX_IMPORTED = 3,
+  SOURCE_IE_IMPORTED = 4,
+  SOURCE_SAFARI_IMPORTED = 5,
+} VisitSource;
 
 typedef int64 VisitID;
+// Structure to hold the mapping between each visit's id and its source.
+typedef std::map<VisitID, VisitSource> VisitSourceMap;
+
+// VisitRow -------------------------------------------------------------------
 
 // Holds all information associated with a specific visit. A visit holds time
 // and referrer information for one time a URL is visited.
diff --git a/chrome/browser/history/history_unittest.cc b/chrome/browser/history/history_unittest.cc
index 063414f..255e466 100644
--- a/chrome/browser/history/history_unittest.cc
+++ b/chrome/browser/history/history_unittest.cc
@@ -415,7 +415,8 @@ TEST_F(HistoryTest, AddPage) {
   const GURL test_url("http://www.google.com/");
   history->AddPage(test_url, NULL, 0, GURL(),
                    PageTransition::MANUAL_SUBFRAME,
-                   history::RedirectList(), false);
+                   history::RedirectList(),
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_url));
   EXPECT_EQ(1, query_url_row_.visit_count());
   EXPECT_EQ(0, query_url_row_.typed_count());
@@ -423,7 +424,8 @@ TEST_F(HistoryTest, AddPage) {
 
   // Add the page once from the main frame (should unhide it).
   history->AddPage(test_url, NULL, 0, GURL(), PageTransition::LINK,
-                   history::RedirectList(), false);
+                   history::RedirectList(),
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_url));
   EXPECT_EQ(2, query_url_row_.visit_count());  // Added twice.
   EXPECT_EQ(0, query_url_row_.typed_count());  // Never typed.
@@ -446,14 +448,16 @@ TEST_F(HistoryTest, AddPageSameTimes) {
   // additions have different timestamps.
   history->AddPage(test_urls[0], now, NULL, 0, GURL(),
                    PageTransition::LINK,
-                   history::RedirectList(), false);
+                   history::RedirectList(),
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_urls[0]));
   EXPECT_EQ(1, query_url_row_.visit_count());
   EXPECT_TRUE(now == query_url_row_.last_visit());  // gtest doesn't like Time
 
   history->AddPage(test_urls[1], now, NULL, 0, GURL(),
                    PageTransition::LINK,
-                   history::RedirectList(), false);
+                   history::RedirectList(),
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_urls[1]));
   EXPECT_EQ(1, query_url_row_.visit_count());
   EXPECT_TRUE(now + TimeDelta::FromMicroseconds(1) ==
@@ -463,7 +467,8 @@ TEST_F(HistoryTest, AddPageSameTimes) {
   history->AddPage(test_urls[2], now + TimeDelta::FromMinutes(1),
                    NULL, 0, GURL(),
                    PageTransition::LINK,
-                   history::RedirectList(), false);
+                   history::RedirectList(),
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_urls[2]));
   EXPECT_EQ(1, query_url_row_.visit_count());
   EXPECT_TRUE(now + TimeDelta::FromMinutes(1) ==
@@ -486,7 +491,8 @@ TEST_F(HistoryTest, AddRedirect) {
   // Add the sequence of pages as a server with no referrer. Note that we need
   // to have a non-NULL page ID scope.
   history->AddPage(first_redirects.back(), MakeFakeHost(1), 0, GURL(),
-                   PageTransition::LINK, first_redirects, true);
+                   PageTransition::LINK, first_redirects,
+                   history::SOURCE_BROWSED,  true);
 
   // The first page should be added once with a link visit type (because we set
   // LINK when we added the original URL, and a referrer of nowhere (0).
@@ -524,7 +530,7 @@ TEST_F(HistoryTest, AddRedirect) {
                    second_redirects[0],
                    static_cast<PageTransition::Type>(PageTransition::LINK |
                        PageTransition::CLIENT_REDIRECT),
-                   second_redirects, true);
+                   second_redirects, history::SOURCE_BROWSED, true);
 
   // The last page (source of the client redirect) should NOT have an
   // additional visit added, because it was a client redirect (normally it
@@ -549,7 +555,8 @@ TEST_F(HistoryTest, Typed) {
   // Add the page once as typed.
   const GURL test_url("http://www.google.com/");
   history->AddPage(test_url, NULL, 0, GURL(), PageTransition::TYPED,
-                   history::RedirectList(), false);
+                   history::RedirectList(),
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_url));
 
   // We should have the same typed & visit count.
@@ -558,7 +565,8 @@ TEST_F(HistoryTest, Typed) {
 
   // Add the page again not typed.
   history->AddPage(test_url, NULL, 0, GURL(), PageTransition::LINK,
-                   history::RedirectList(), false);
+                   history::RedirectList(),
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_url));
 
   // The second time should not have updated the typed count.
@@ -568,7 +576,7 @@ TEST_F(HistoryTest, Typed) {
   // Add the page again as a generated URL.
   history->AddPage(test_url, NULL, 0, GURL(),
                    PageTransition::GENERATED, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_url));
 
   // This should have worked like a link click.
@@ -578,7 +586,7 @@ TEST_F(HistoryTest, Typed) {
   // Add the page again as a reload.
   history->AddPage(test_url, NULL, 0, GURL(),
                    PageTransition::RELOAD, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
   EXPECT_TRUE(QueryURL(history, test_url));
 
   // This should not have incremented any visit counts.
@@ -593,7 +601,7 @@ TEST_F(HistoryTest, SetTitle) {
 
   // Add a URL.
   const GURL existing_url("http://www.google.com/");
-  history->AddPage(existing_url);
+  history->AddPage(existing_url, history::SOURCE_BROWSED);
 
   // Set some title.
   const string16 existing_title = UTF8ToUTF16("Google");
@@ -628,7 +636,7 @@ TEST_F(HistoryTest, Segments) {
   const GURL existing_url("http://www.google.com/");
   history->AddPage(existing_url, scope, 0, GURL(),
                    PageTransition::TYPED, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
 
   // Make sure a segment was created.
   history->QuerySegmentUsageSince(
@@ -647,7 +655,7 @@ TEST_F(HistoryTest, Segments) {
   const GURL link_url("http://yahoo.com/");
   history->AddPage(link_url, scope, 0, GURL(),
                    PageTransition::LINK, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
 
   // Query again
   history->QuerySegmentUsageSince(
@@ -665,7 +673,7 @@ TEST_F(HistoryTest, Segments) {
   // Add a page linked from existing_url.
   history->AddPage(GURL("http://www.google.com/foo"), scope, 3, existing_url,
                    PageTransition::LINK, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
 
   // Query again
   history->QuerySegmentUsageSince(
@@ -699,7 +707,8 @@ TEST_F(HistoryTest, Thumbnails) {
   static const double boringness = 0.25;
 
   const GURL url("http://www.google.com/thumbnail_test/");
-  history->AddPage(url);  // Must be visited before adding a thumbnail.
+  // Must be visited before adding a thumbnail.
+  history->AddPage(url, history::SOURCE_BROWSED);
   history->SetPageThumbnail(url, *thumbnail,
                             ThumbnailScore(boringness, true, true));
 
@@ -766,10 +775,10 @@ TEST_F(HistoryTest, MostVisitedURLs) {
   // Add two pages.
   history->AddPage(url0, scope, 0, GURL(),
                    PageTransition::TYPED, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
   history->AddPage(url1, scope, 0, GURL(),
                    PageTransition::TYPED, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
   history->QueryMostVisitedURLs(20, 90, &consumer_,
                                 NewCallback(static_cast<HistoryTest*>(this),
                                     &HistoryTest::OnMostVisitedURLsAvailable));
@@ -782,7 +791,7 @@ TEST_F(HistoryTest, MostVisitedURLs) {
   // Add another page.
   history->AddPage(url2, scope, 0, GURL(),
                    PageTransition::TYPED, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
   history->QueryMostVisitedURLs(20, 90, &consumer_,
                                 NewCallback(static_cast<HistoryTest*>(this),
                                     &HistoryTest::OnMostVisitedURLsAvailable));
@@ -796,7 +805,7 @@ TEST_F(HistoryTest, MostVisitedURLs) {
   // Revisit url2, making it the top URL.
   history->AddPage(url2, scope, 0, GURL(),
                    PageTransition::TYPED, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
   history->QueryMostVisitedURLs(20, 90, &consumer_,
                                 NewCallback(static_cast<HistoryTest*>(this),
                                     &HistoryTest::OnMostVisitedURLsAvailable));
@@ -810,7 +819,7 @@ TEST_F(HistoryTest, MostVisitedURLs) {
   // Revisit url1, making it the top URL.
   history->AddPage(url1, scope, 0, GURL(),
                    PageTransition::TYPED, history::RedirectList(),
-                   false);
+                   history::SOURCE_BROWSED, false);
   history->QueryMostVisitedURLs(20, 90, &consumer_,
                                 NewCallback(static_cast<HistoryTest*>(this),
                                     &HistoryTest::OnMostVisitedURLsAvailable));
@@ -829,7 +838,7 @@ TEST_F(HistoryTest, MostVisitedURLs) {
   // Visit url4 using redirects.
   history->AddPage(url4, scope, 0, GURL(),
                    PageTransition::TYPED, redirects,
-                   false);
+                   history::SOURCE_BROWSED, false);
   history->QueryMostVisitedURLs(20, 90, &consumer_,
                                 NewCallback(static_cast<HistoryTest*>(this),
                                     &HistoryTest::OnMostVisitedURLsAvailable));
@@ -887,7 +896,8 @@ HistoryAddPageArgs* MakeAddArgs(const GURL& url) {
                                 0,
                                 GURL(),
                                 history::RedirectList(),
-                                PageTransition::TYPED, false);
+                                PageTransition::TYPED,
+                                history::SOURCE_BROWSED, false);
 }
 
 // Convenience version of the above to convert a char string.
diff --git a/chrome/browser/history/text_database_manager_unittest.cc b/chrome/browser/history/text_database_manager_unittest.cc
index 8e7f27e..1ec7744 100644
--- a/chrome/browser/history/text_database_manager_unittest.cc
+++ b/chrome/browser/history/text_database_manager_unittest.cc
@@ -79,7 +79,7 @@ void AddAllPages(TextDatabaseManager& manager, VisitDatabase* visit_db,
   visit_row.transition = 0;
   visit_row.segment_id = 0;
   visit_row.is_indexed = false;
-  VisitID visit_id = visit_db->AddVisit(&visit_row);
+  VisitID visit_id = visit_db->AddVisit(&visit_row, SOURCE_BROWSED);
 
   times->push_back(visit_row.visit_time);
   manager.AddPageData(GURL(kURL1), visit_row.url_id, visit_row.visit_id,
@@ -89,7 +89,7 @@ void AddAllPages(TextDatabaseManager& manager, VisitDatabase* visit_db,
   exploded.day_of_month++;
   visit_row.url_id = 2;
   visit_row.visit_time = Time::FromUTCExploded(exploded);
-  visit_id = visit_db->AddVisit(&visit_row);
+  visit_id = visit_db->AddVisit(&visit_row, SOURCE_BROWSED);
   times->push_back(visit_row.visit_time);
   manager.AddPageData(GURL(kURL2), visit_row.url_id, visit_row.visit_id,
                       visit_row.visit_time, UTF8ToUTF16(kTitle2),
@@ -98,7 +98,7 @@ void AddAllPages(TextDatabaseManager& manager, VisitDatabase* visit_db,
   exploded.day_of_month++;
   visit_row.url_id = 2;
   visit_row.visit_time = Time::FromUTCExploded(exploded);
-  visit_id = visit_db->AddVisit(&visit_row);
+  visit_id = visit_db->AddVisit(&visit_row, SOURCE_BROWSED);
   times->push_back(visit_row.visit_time);
   manager.AddPageData(GURL(kURL3), visit_row.url_id, visit_row.visit_id,
                       visit_row.visit_time, UTF8ToUTF16(kTitle3),
@@ -108,7 +108,7 @@ void AddAllPages(TextDatabaseManager& manager, VisitDatabase* visit_db,
   exploded.month++;
   visit_row.url_id = 2;
   visit_row.visit_time = Time::FromUTCExploded(exploded);
-  visit_id = visit_db->AddVisit(&visit_row);
+  visit_id = visit_db->AddVisit(&visit_row, SOURCE_BROWSED);
   times->push_back(visit_row.visit_time);
   manager.AddPageData(GURL(kURL4), visit_row.url_id, visit_row.visit_id,
                       visit_row.visit_time, UTF8ToUTF16(kTitle4),
@@ -117,7 +117,7 @@ void AddAllPages(TextDatabaseManager& manager, VisitDatabase* visit_db,
   exploded.day_of_month++;
   visit_row.url_id = 2;
   visit_row.visit_time = Time::FromUTCExploded(exploded);
-  visit_id = visit_db->AddVisit(&visit_row);
+  visit_id = visit_db->AddVisit(&visit_row, SOURCE_BROWSED);
   times->push_back(visit_row.visit_time);
   manager.AddPageData(GURL(kURL5), visit_row.url_id, visit_row.visit_id,
                       visit_row.visit_time, UTF8ToUTF16(kTitle5),
@@ -127,7 +127,7 @@ void AddAllPages(TextDatabaseManager& manager, VisitDatabase* visit_db,
   exploded.day_of_month++;
   visit_row.url_id = 2;
   visit_row.visit_time = Time::FromUTCExploded(exploded);
-  visit_id = visit_db->AddVisit(&visit_row);
+  visit_id = visit_db->AddVisit(&visit_row, SOURCE_BROWSED);
   times->push_back(visit_row.visit_time);
   manager.AddPageData(GURL(kURL1), visit_row.url_id, visit_row.visit_id,
                       visit_row.visit_time, UTF8ToUTF16(kTitle1),
@@ -242,7 +242,7 @@ TEST_F(TextDatabaseManagerTest, InsertCompleteVisit) {
   visit.transition = PageTransition::LINK;
   visit.segment_id = 0;
   visit.is_indexed = false;
-  visit_db.AddVisit(&visit);
+  visit_db.AddVisit(&visit, SOURCE_BROWSED);
 
   // Add a full text indexed entry for that visit.
   const GURL url(kURL2);
@@ -335,7 +335,7 @@ TEST_F(TextDatabaseManagerTest, PartialComplete) {
   VisitRow visit_row;
   visit_row.url_id = url_id;
   visit_row.visit_time = added_time;
-  visit_db.AddVisit(&visit_row);
+  visit_db.AddVisit(&visit_row, SOURCE_BROWSED);
 
   // Add a URL with no title or body, and say that it expired.
   manager.AddPageURL(url, 0, 0, added_time);
diff --git a/chrome/browser/history/thumbnail_database.cc b/chrome/browser/history/thumbnail_database.cc
index 979accf..ecc7a3c 100644
--- a/chrome/browser/history/thumbnail_database.cc
+++ b/chrome/browser/history/thumbnail_database.cc
@@ -499,7 +499,8 @@ bool ThumbnailDatabase::RenameAndDropThumbnails(const FilePath& old_db_file,
   favicons.Close();
 
   // Can't attach within a transaction.
-  CommitTransaction();
+  if (transaction_nesting())
+    CommitTransaction();
 
   // Attach new DB.
   {
diff --git a/chrome/browser/history/visit_database.cc b/chrome/browser/history/visit_database.cc
index 75c91ee..d0156c2 100644
--- a/chrome/browser/history/visit_database.cc
+++ b/chrome/browser/history/visit_database.cc
@@ -11,6 +11,7 @@
 
 #include "app/sql/statement.h"
 #include "base/logging.h"
+#include "base/string_number_conversions.h"
 #include "chrome/browser/history/url_database.h"
 #include "chrome/common/page_transition_types.h"
 #include "chrome/common/url_constants.h"
@@ -50,6 +51,17 @@ bool VisitDatabase::InitVisitTable() {
       return false;
   }
 
+  // Visit source table contains the source information for all the visits. To
+  // save space, we do not record those user browsed visits which would be the
+  // majority in this table. Only other sources are recorded.
+  // Due to the tight relationship between visit_source and visits table, they
+  // should be created and dropped at the same time.
+  if (!GetDB().DoesTableExist("visit_source")) {
+    if (!GetDB().Execute("CREATE TABLE visit_source("
+                         "id INTEGER PRIMARY KEY,source INTEGER NOT NULL)"))
+        return false;
+  }
+
   // Index over url so we can quickly find visits for a page. This will just
   // fail if it already exists and we'll ignore it.
   GetDB().Execute("CREATE INDEX visits_url_index ON visits (url)");
@@ -67,6 +79,7 @@ bool VisitDatabase::InitVisitTable() {
 }
 
 bool VisitDatabase::DropVisitTable() {
+  GetDB().Execute("DROP TABLE visit_source");
   // This will also drop the indices over the table.
   return GetDB().Execute("DROP TABLE visits");
 }
@@ -93,7 +106,7 @@ void VisitDatabase::FillVisitVector(sql::Statement& statement,
   }
 }
 
-VisitID VisitDatabase::AddVisit(VisitRow* visit) {
+VisitID VisitDatabase::AddVisit(VisitRow* visit, VisitSource source) {
   sql::Statement statement(GetDB().GetCachedStatement(SQL_FROM_HERE,
       "INSERT INTO visits "
       "(url, visit_time, from_visit, transition, segment_id, is_indexed) "
@@ -111,6 +124,20 @@ VisitID VisitDatabase::AddVisit(VisitRow* visit) {
     return 0;
 
   visit->visit_id = GetDB().GetLastInsertRowId();
+
+  if (source != SOURCE_BROWSED) {
+    // Record the source of this visit when it is not browsed.
+    sql::Statement statement1(GetDB().GetCachedStatement(SQL_FROM_HERE,
+        "INSERT INTO visit_source (id, source) VALUES (?,?)"));
+    if (!statement1.is_valid())
+      return 0;
+
+    statement1.BindInt64(0, visit->visit_id);
+    statement1.BindInt64(1, source);
+    if (!statement1.Run())
+      return 0;
+  }
+
   return visit->visit_id;
 }
 
@@ -132,6 +159,16 @@ void VisitDatabase::DeleteVisit(const VisitRow& visit) {
     return;
   del.BindInt64(0, visit.visit_id);
   del.Run();
+
+  // Try to delete the entry in visit_source table as well.
+  // If the visit was browsed, there is no corresponding entry in visit_source
+  // table, and nothing will be deleted.
+  del.Assign(GetDB().GetCachedStatement(SQL_FROM_HERE,
+             "DELETE FROM visit_source WHERE id=?"));
+  if (!del.is_valid())
+    return;
+  del.BindInt64(0, visit.visit_id);
+  del.Run();
 }
 
 bool VisitDatabase::GetRowForVisit(VisitID visit_id, VisitRow* out_visit) {
@@ -436,4 +473,42 @@ bool VisitDatabase::GetStartDate(base::Time* first_visit) {
   return true;
 }
 
+void VisitDatabase::GetVisitsSource(const VisitVector& visits,
+                                    VisitSourceMap* sources) {
+  DCHECK(sources);
+  sources->clear();
+
+  // We query the source in batch. Here defines the batch size.
+  const size_t batch_size = 500;
+  size_t visits_size = visits.size();
+
+  size_t start_index = 0, end_index = 0;
+  while (end_index < visits_size) {
+    start_index = end_index;
+    end_index = end_index + batch_size < visits_size ? end_index + batch_size
+                                                     : visits_size;
+
+    // Compose the sql statement with a list of ids.
+    std::string sql = "SELECT id,source FROM visit_source ";
+    sql.append("WHERE id IN (");
+    // Append all the ids in the statement.
+    for (size_t j = start_index; j < end_index; j++) {
+      if (j != start_index)
+        sql.push_back(',');
+      sql.append(base::Int64ToString(visits[j].visit_id));
+    }
+    sql.append(") ORDER BY id");
+    sql::Statement statement(GetDB().GetUniqueStatement(sql.c_str()));
+    if (!statement)
+      return;
+
+    // Get the source entries out of the query result.
+    while (statement.Step()) {
+      std::pair<VisitID, VisitSource> source_entry(statement.ColumnInt64(0),
+          static_cast<VisitSource>(statement.ColumnInt(1)));
+      sources->insert(source_entry);
+    }
+  }
+}
+
 }  // namespace history
diff --git a/chrome/browser/history/visit_database.h b/chrome/browser/history/visit_database.h
index 3731c4a..0e97cac 100644
--- a/chrome/browser/history/visit_database.h
+++ b/chrome/browser/history/visit_database.h
@@ -34,8 +34,9 @@ class VisitDatabase {
 
   // Adds a line to the visit database with the given information, returning
   // the added row ID on success, 0 on failure. The given visit is updated with
-  // the new row ID on success.
-  VisitID AddVisit(VisitRow* visit);
+  // the new row ID on success. In addition, adds its source into visit_source
+  // table.
+  VisitID AddVisit(VisitRow* visit, VisitSource source);
 
   // Deletes the given visit from the database. If a visit with the given ID
   // doesn't exist, it will not do anything.
@@ -144,6 +145,10 @@ class VisitDatabase {
   // Get the time of the first item in our database.
   bool GetStartDate(base::Time* first_visit);
 
+  // Get the source information about the given visits.
+  void GetVisitsSource(const VisitVector& visits,
+                       VisitSourceMap* sources);
+
  protected:
   // Returns the database for the functions in this interface.
   virtual sql::Connection& GetDB() = 0;
diff --git a/chrome/browser/history/visit_database_unittest.cc b/chrome/browser/history/visit_database_unittest.cc
index ebc2e1b..28a0e15 100644
--- a/chrome/browser/history/visit_database_unittest.cc
+++ b/chrome/browser/history/visit_database_unittest.cc
@@ -73,19 +73,19 @@ class VisitDatabaseTest : public PlatformTest,
 TEST_F(VisitDatabaseTest, Add) {
   // Add one visit.
   VisitRow visit_info1(1, Time::Now(), 0, PageTransition::LINK, 0);
-  EXPECT_TRUE(AddVisit(&visit_info1));
+  EXPECT_TRUE(AddVisit(&visit_info1, SOURCE_BROWSED));
 
   // Add second visit for the same page.
   VisitRow visit_info2(visit_info1.url_id,
       visit_info1.visit_time + TimeDelta::FromSeconds(1), 1,
       PageTransition::TYPED, 0);
-  EXPECT_TRUE(AddVisit(&visit_info2));
+  EXPECT_TRUE(AddVisit(&visit_info2, SOURCE_BROWSED));
 
   // Add third visit for a different page.
   VisitRow visit_info3(2,
       visit_info1.visit_time + TimeDelta::FromSeconds(2), 0,
       PageTransition::LINK, 0);
-  EXPECT_TRUE(AddVisit(&visit_info3));
+  EXPECT_TRUE(AddVisit(&visit_info3, SOURCE_BROWSED));
 
   // Query the first two.
   std::vector<VisitRow> matches;
@@ -104,17 +104,17 @@ TEST_F(VisitDatabaseTest, Delete) {
   static const int kTime1 = 1000;
   VisitRow visit_info1(1, Time::FromInternalValue(kTime1), 0,
                        PageTransition::LINK, 0);
-  EXPECT_TRUE(AddVisit(&visit_info1));
+  EXPECT_TRUE(AddVisit(&visit_info1, SOURCE_BROWSED));
 
   static const int kTime2 = kTime1 + 1;
   VisitRow visit_info2(1, Time::FromInternalValue(kTime2),
                        visit_info1.visit_id, PageTransition::LINK, 0);
-  EXPECT_TRUE(AddVisit(&visit_info2));
+  EXPECT_TRUE(AddVisit(&visit_info2, SOURCE_BROWSED));
 
   static const int kTime3 = kTime2 + 1;
   VisitRow visit_info3(1, Time::FromInternalValue(kTime3),
                        visit_info2.visit_id, PageTransition::LINK, 0);
-  EXPECT_TRUE(AddVisit(&visit_info3));
+  EXPECT_TRUE(AddVisit(&visit_info3, SOURCE_BROWSED));
 
   // First make sure all the visits are there.
   std::vector<VisitRow> matches;
@@ -140,7 +140,7 @@ TEST_F(VisitDatabaseTest, Delete) {
 TEST_F(VisitDatabaseTest, Update) {
   // Make something in the database.
   VisitRow original(1, Time::Now(), 23, 22, 19);
-  AddVisit(&original);
+  AddVisit(&original, SOURCE_BROWSED);
 
   // Mutate that row.
   VisitRow modification(original);
@@ -167,7 +167,7 @@ TEST_F(VisitDatabaseTest, GetVisibleVisitsInRange) {
                                         PageTransition::CHAIN_END),
       0);
   visit_info1.visit_id = 1;
-  EXPECT_TRUE(AddVisit(&visit_info1));
+  EXPECT_TRUE(AddVisit(&visit_info1, SOURCE_BROWSED));
 
   // Add second visit for the same page.
   VisitRow visit_info2(visit_info1.url_id,
@@ -177,7 +177,7 @@ TEST_F(VisitDatabaseTest, GetVisibleVisitsInRange) {
                                         PageTransition::CHAIN_END),
       0);
   visit_info2.visit_id = 2;
-  EXPECT_TRUE(AddVisit(&visit_info2));
+  EXPECT_TRUE(AddVisit(&visit_info2, SOURCE_BROWSED));
 
   // Add third visit for a different page.
   VisitRow visit_info3(2,
@@ -186,7 +186,7 @@ TEST_F(VisitDatabaseTest, GetVisibleVisitsInRange) {
                                         PageTransition::CHAIN_START),
       0);
   visit_info3.visit_id = 3;
-  EXPECT_TRUE(AddVisit(&visit_info3));
+  EXPECT_TRUE(AddVisit(&visit_info3, SOURCE_BROWSED));
 
   // Add a redirect visit from the last page.
   VisitRow visit_info4(3,
@@ -195,7 +195,7 @@ TEST_F(VisitDatabaseTest, GetVisibleVisitsInRange) {
                                         PageTransition::CHAIN_END),
       0);
   visit_info4.visit_id = 4;
-  EXPECT_TRUE(AddVisit(&visit_info4));
+  EXPECT_TRUE(AddVisit(&visit_info4, SOURCE_BROWSED));
 
   // Add a subframe visit.
   VisitRow visit_info5(4,
@@ -205,7 +205,7 @@ TEST_F(VisitDatabaseTest, GetVisibleVisitsInRange) {
                                         PageTransition::CHAIN_END),
       0);
   visit_info5.visit_id = 5;
-  EXPECT_TRUE(AddVisit(&visit_info5));
+  EXPECT_TRUE(AddVisit(&visit_info5, SOURCE_BROWSED));
 
   // Query the visits for all time, we should not get the first (duplicate of
   // the second) or the redirect or subframe visits.
@@ -227,4 +227,37 @@ TEST_F(VisitDatabaseTest, GetVisibleVisitsInRange) {
   ASSERT_EQ(static_cast<size_t>(1), results.size());
   EXPECT_TRUE(IsVisitInfoEqual(results[0], visit_info4));
 }
+
+TEST_F(VisitDatabaseTest, VisitSource) {
+  // Add visits.
+  VisitRow visit_info1(111, Time::Now(), 0, PageTransition::LINK, 0);
+  ASSERT_TRUE(AddVisit(&visit_info1, SOURCE_BROWSED));
+
+  VisitRow visit_info2(112, Time::Now(), 1, PageTransition::TYPED, 0);
+  ASSERT_TRUE(AddVisit(&visit_info2, SOURCE_SYNCED));
+
+  VisitRow visit_info3(113, Time::Now(), 0, PageTransition::TYPED, 0);
+  ASSERT_TRUE(AddVisit(&visit_info3, SOURCE_EXTENSION));
+
+  // Query each visit.
+  std::vector<VisitRow> matches;
+  ASSERT_TRUE(GetVisitsForURL(111, &matches));
+  ASSERT_EQ(1U, matches.size());
+  VisitSourceMap sources;
+  GetVisitsSource(matches, &sources);
+  EXPECT_EQ(0U, sources.size());
+
+  ASSERT_TRUE(GetVisitsForURL(112, &matches));
+  ASSERT_EQ(1U, matches.size());
+  GetVisitsSource(matches, &sources);
+  ASSERT_EQ(1U, sources.size());
+  EXPECT_EQ(SOURCE_SYNCED, sources[matches[0].visit_id]);
+
+  ASSERT_TRUE(GetVisitsForURL(113, &matches));
+  ASSERT_EQ(1U, matches.size());
+  GetVisitsSource(matches, &sources);
+  ASSERT_EQ(1U, sources.size());
+  EXPECT_EQ(SOURCE_EXTENSION, sources[matches[0].visit_id]);
+}
+
 }  // namespace history