Proof of concept implementation of context based history filtering.

components/history/core/browser/url_database.cc

Index: components/history/core/browser/url_database.cc
diff --git a/components/history/core/browser/url_database.cc b/components/history/core/browser/url_database.cc
index 65ac67e8e9717e9a5f8511b7fd3d7d0e2b5e4a95..024bea27b3a8a1f1e4e940c8241b660a6c08cafc 100644
--- a/components/history/core/browser/url_database.cc
+++ b/components/history/core/browser/url_database.cc
@@ -68,7 +68,8 @@ void URLDatabase::FillURLRow(sql::Statement& s, URLRow* i) {
   i->visit_count_ = s.ColumnInt(3);
   i->typed_count_ = s.ColumnInt(4);
   i->last_visit_ = base::Time::FromInternalValue(s.ColumnInt64(5));
-  i->hidden_ = s.ColumnInt(6) != 0;
+  i->context_ = static_cast<history::HistoryContext>(s.ColumnInt(6));
+  i->hidden_ = s.ColumnInt(7) != 0;
 }
 
 bool URLDatabase::GetURLRow(URLID url_id, URLRow* info) {
@@ -115,15 +116,16 @@ URLID URLDatabase::GetRowForURL(const GURL& url, URLRow* info) {
 
 bool URLDatabase::UpdateURLRow(URLID url_id, const URLRow& info) {
   sql::Statement statement(GetDB().GetCachedStatement(SQL_FROM_HERE,
-      "UPDATE urls SET title=?,visit_count=?,typed_count=?,last_visit_time=?,"
+      "UPDATE urls SET title=?,visit_count=?,typed_count=?,last_visit_time=?,context=?,"
         "hidden=?"
       "WHERE id=?"));
   statement.BindString16(0, info.title());
   statement.BindInt(1, info.visit_count());
   statement.BindInt(2, info.typed_count());
   statement.BindInt64(3, info.last_visit().ToInternalValue());
-  statement.BindInt(4, info.hidden() ? 1 : 0);
-  statement.BindInt64(5, url_id);
+  statement.BindInt(4, info.context());
+  statement.BindInt(5, info.hidden() ? 1 : 0);
+  statement.BindInt64(6, url_id);
 
   return statement.Run() && GetDB().GetLastChangeCount() > 0;
 }
@@ -603,6 +605,7 @@ bool URLDatabase::CreateURLTable(bool is_temporary) {
       "visit_count INTEGER DEFAULT 0 NOT NULL,"
       "typed_count INTEGER DEFAULT 0 NOT NULL,"
       "last_visit_time INTEGER NOT NULL,"
+      "context INTEGER DEFAULT 0 NOT NULL,"
       "hidden INTEGER DEFAULT 0 NOT NULL,"
       "favicon_id INTEGER DEFAULT 0 NOT NULL)"); // favicon_id is not used now.