Revert CL 117933003. Re-add resource speculative prefetching code.

chrome/browser/predictors/predictor_database.cc

Index: chrome/browser/predictors/predictor_database.cc
diff --git a/chrome/browser/predictors/predictor_database.cc b/chrome/browser/predictors/predictor_database.cc
index eb2bf5cda43a289e2931e9f17f2d574715e6e3b8..9f8460a100f6c0c118ccf810589c75dbae2c2bac 100644
--- a/chrome/browser/predictors/predictor_database.cc
+++ b/chrome/browser/predictors/predictor_database.cc
@@ -12,6 +12,8 @@
 #include "base/strings/stringprintf.h"
 #include "chrome/browser/predictors/autocomplete_action_predictor_table.h"
 #include "chrome/browser/predictors/logged_in_predictor_table.h"
+#include "chrome/browser/predictors/resource_prefetch_predictor.h"
+#include "chrome/browser/predictors/resource_prefetch_predictor_tables.h"
 #include "chrome/browser/prerender/prerender_field_trial.h"
 #include "chrome/browser/profiles/profile.h"
 #include "content/public/browser/browser_thread.h"
@@ -50,6 +52,7 @@ class PredictorDatabaseInternal
   // Cancels pending DB transactions. Should only be called on the UI thread.
   void SetCancelled();
 
+  bool is_resource_prefetch_predictor_enabled_;
   base::FilePath db_path_;
   scoped_ptr<sql::Connection> db_;
 
@@ -57,6 +60,7 @@ class PredictorDatabaseInternal
   // to using a WeakPtr instead.
   scoped_refptr<AutocompleteActionPredictorTable> autocomplete_table_;
   scoped_refptr<LoggedInPredictorTable> logged_in_table_;
+  scoped_refptr<ResourcePrefetchPredictorTables> resource_prefetch_tables_;
 
   DISALLOW_COPY_AND_ASSIGN(PredictorDatabaseInternal);
 };
@@ -66,8 +70,12 @@ PredictorDatabaseInternal::PredictorDatabaseInternal(Profile* profile)
     : db_path_(profile->GetPath().Append(kPredictorDatabaseName)),
       db_(new sql::Connection()),
       autocomplete_table_(new AutocompleteActionPredictorTable()),
-      logged_in_table_(new LoggedInPredictorTable()) {
+      logged_in_table_(new LoggedInPredictorTable()),
+      resource_prefetch_tables_(new ResourcePrefetchPredictorTables()) {
   db_->set_histogram_tag("Predictor");
+  ResourcePrefetchPredictorConfig config;
+  is_resource_prefetch_predictor_enabled_ =
+      IsSpeculativeResourcePrefetchingEnabled(profile, &config);
 }
 
 PredictorDatabaseInternal::~PredictorDatabaseInternal() {
@@ -89,6 +97,7 @@ void PredictorDatabaseInternal::Initialize() {
 
   autocomplete_table_->Initialize(db_.get());
   logged_in_table_->Initialize(db_.get());
+  resource_prefetch_tables_->Initialize(db_.get());
 
   LogDatabaseStats();
 }
@@ -99,6 +108,7 @@ void PredictorDatabaseInternal::SetCancelled() {
 
   autocomplete_table_->SetCancelled();
   logged_in_table_->SetCancelled();
+  resource_prefetch_tables_->SetCancelled();
 }
 
 void PredictorDatabaseInternal::LogDatabaseStats() {
@@ -113,6 +123,8 @@ void PredictorDatabaseInternal::LogDatabaseStats() {
 
   autocomplete_table_->LogDatabaseStats();
   logged_in_table_->LogDatabaseStats();
+  if (is_resource_prefetch_predictor_enabled_)
+    resource_prefetch_tables_->LogDatabaseStats();
 }
 
 PredictorDatabase::PredictorDatabase(Profile* profile)
@@ -138,6 +150,11 @@ scoped_refptr<LoggedInPredictorTable>
   return db_->logged_in_table_;
 }
 
+scoped_refptr<ResourcePrefetchPredictorTables>
+    PredictorDatabase::resource_prefetch_tables() {
+  return db_->resource_prefetch_tables_;
+}
+
 sql::Connection* PredictorDatabase::GetDatabase() {
   return db_->db_.get();
 }