Handle interface to prerenders.

chrome/browser/predictors/autocomplete_action_predictor.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_PREDICTORS_AUTOCOMPLETE_ACTION_PREDICTOR_H_
 #define CHROME_BROWSER_PREDICTORS_AUTOCOMPLETE_ACTION_PREDICTOR_H_
 #pragma once
 
 #include <map>
 
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "base/string16.h"
 #include "chrome/browser/history/history_types.h"
 #include "chrome/browser/predictors/autocomplete_action_predictor_table.h"
 #include "chrome/browser/profiles/profile_keyed_service.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 #include "googleurl/src/gurl.h"
+#include "ui/gfx/size.h"
 
 struct AutocompleteLog;
 struct AutocompleteMatch;
 class AutocompleteResult;
 class HistoryService;
 class PredictorsHandler;
 class Profile;
 
+namespace content {
+  class SessionStorageNamespace;
+}
+
 namespace history {
 class URLDatabase;
 }
 
+namespace prerender {
+class PrerenderHandle;
+}
+
 namespace predictors {
 
 // This class is responsible for determining the correct predictive network
 // action to take given for a given AutocompleteMatch and entered text. It can
 // be instantiated for both normal and incognito profiles.  For normal profiles,
 // it uses an AutocompleteActionPredictorTable accessed asynchronously on the DB
 // thread to permanently store the data used to make predictions, and keeps
 // local caches of that data to be able to make predictions synchronously on the
 // UI thread where it lives.  For incognito profiles, there is no table; the
 // local caches are copied from the main profile at creation and from there on
@@ skipping 29 matching lines @@
 
   // Return the recommended action given |user_text|, the text the user has
   // entered in the Omnibox, and |match|, the suggestion from Autocomplete.
   // This method uses information from the ShortcutsBackend including how much
   // of the matching entry the user typed, and how long it's been since the user
   // visited the matching URL, to calculate a score between 0 and 1. This score
   // is then mapped to an Action.
   Action RecommendAction(const string16& user_text,
                          const AutocompleteMatch& match) const;
 
+  // Begin prerendering |url| with |session_storage_namespace|. The |size| gives
+  // the initial size for the target prerender. The predictor will run at most
+  // one prerender at a time, so launching a prerender will cancel our previous
+  // prerenders (if any).
+  void StartPrerendering(
+      const GURL& url,
+      content::SessionStorageNamespace* session_storage_namespace,
+      gfx::Size size);
+
   // Return true if the suggestion type warrants a TCP/IP preconnection.
   // i.e., it is now quite likely that the user will select the related domain.
   static bool IsPreconnectable(const AutocompleteMatch& match);
 
  private:
   friend class AutocompleteActionPredictorTest;
   friend class ::PredictorsHandler;
 
   struct TransitionalMatch {
     TransitionalMatch();
@@ skipping 100 matching lines @@
   AutocompleteActionPredictor* incognito_predictor_;
 
   // The backing data store.  This is NULL for incognito-owned predictors.
   scoped_refptr<AutocompleteActionPredictorTable> table_;
 
   content::NotificationRegistrar notification_registrar_;
 
   // This is cleared after every Omnibox navigation.
   std::vector<TransitionalMatch> transitional_matches_;
 
+  scoped_ptr<prerender::PrerenderHandle> prerender_handle_;
+
   // This allows us to predict the effect of confidence threshold changes on
   // accuracy.  This is cleared after every omnibox navigation.
   mutable std::vector<std::pair<GURL, double> > tracked_urls_;
 
   // Local caches of the data store.  For incognito-owned predictors this is the
   // only copy of the data.
   DBCacheMap db_cache_;
   DBIdCacheMap db_id_cache_;
 
   bool initialized_;
 
   DISALLOW_COPY_AND_ASSIGN(AutocompleteActionPredictor);
 };
 
 }  // namespace predictors
 
 #endif  // CHROME_BROWSER_PREDICTORS_AUTOCOMPLETE_ACTION_PREDICTOR_H_