Instant: Use only one hidden WebContents per profile.

chrome/browser/instant/instant_service.h

 // Copyright 2013 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_INSTANT_INSTANT_SERVICE_H_
 #define CHROME_BROWSER_INSTANT_INSTANT_SERVICE_H_
 
+#include <list>
 #include <set>
+#include <string>
+#include <utility>
+#include <vector>
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/observer_list.h"
+#include "base/prefs/public/pref_change_registrar.h"
+#include "base/string16.h"
+#include "chrome/browser/history/history_types.h"
 #include "chrome/browser/profiles/profile_keyed_service.h"
+#include "chrome/common/instant_types.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
 
 class InstantIOContext;
+class InstantPreloader;
+class InstantServiceObserver;
 class Profile;
+class ThemeService;
 
-// Tracks render process host IDs that are associated with Instant.
+namespace history {
+class TopSites;
+}
+
+// Tracks Instant-related per-profile things, such as render process host IDs,

[samarth, 2013/03/11 19:03:24]

nit: Tracks per-profile Instant-related things

+// chrome://settings preferences, omnibox size, theme background, etc.
 class InstantService : public ProfileKeyedService,
                        public content::NotificationObserver {
  public:
   explicit InstantService(Profile* profile);
   virtual ~InstantService();
 
-  // Add, remove, and query RenderProcessHost IDs that are associated with
-  // Instant processes.
+  Profile* profile() const { return profile_; }
+  InstantPreloader* preloader() const { return preloader_.get(); }
+
+  typedef std::list<std::pair<int64, std::string> > DebugEventsList;
+  const DebugEventsList& debug_events() const {
+    return debug_events_;
+  }
+  void LogDebugEvent(const std::string& message);
+  void ClearDebugEvents();
+
+  void AddObserver(InstantServiceObserver* observer);
+  void RemoveObserver(InstantServiceObserver* observer);
+
+  // Query and modify RenderProcessHost IDs associated with Instant processes.
+  bool IsInstantProcess(int process_id) const;
   void AddInstantProcess(int process_id);
-  bool IsInstantProcess(int process_id) const;
+  void RemoveInstantProcess(int process_id);
 
 #if defined(UNIT_TEST)
-  int GetInstantProcessCount() const {
-    return process_ids_.size();
-  }
+  int GetInstantProcessCount() const { return process_ids_.size(); }
 #endif
 
+  const string16& omnibox_font_name() const { return omnibox_font_name_; }
+  size_t omnibox_font_size() const { return omnibox_font_size_; }
+
+  // The omnibox start margin is the same in all browser windows in a profile,
+  // so it can be considered a per-profile setting. It is used in contexts
+  // where there are no browser windows available, such as in InstantPreloader.
+  // However, since InstantService has no knowledge of browser windows, this
+  // information must be passed to us by say, an InstantController. If there
+  // are multiple windows open, and the margin changes, each instance of
+  // InstantController will call us with this info, but it shouldn't be a
+  // problem since, as above, the info will be the same in all calls.
+  int omnibox_start_margin() const { return omnibox_start_margin_; }
+  void set_omnibox_start_margin(int omnibox_start_margin) {
+    omnibox_start_margin_ = omnibox_start_margin;
+  }
+
+  const ThemeBackgroundInfo& theme_info() const { return theme_info_; }
+
+  const std::vector<MostVisitedItem>& most_visited_items() const {
+    return most_visited_items_;
+  }
+
+  void InstantSupportDetermined();
+
  private:
-  // Overridden from ProfileKeyedService:
-  virtual void Shutdown() OVERRIDE;
-
   // Overridden from content::NotificationObserver:
   virtual void Observe(int type,
                        const content::NotificationSource& source,
                        const content::NotificationDetails& details) OVERRIDE;
 
+  // Called whenever one of the prefs we are monitoring changes. If the
+  // effective status of Instant or the Instant pref changes as a result, causes
+  // InstantStatusChanged() to be called on |observers_|.
+  void PrefChanged(const std::string& pref_name);
+
+  // Called whenever theme information changes. Causes ThemeInfoChanged() to be
+  // called on |observers_|.
+  void ParseTheme(ThemeService* theme_service);
+
+  // Called whenever the Most Visited Items in history changed. This kicks off
+  // a request to fetch the actual items.
+  void RequestMostVisitedItems(history::TopSites* top_sites);
+
+  // Called when the actual Most Visited Items are available. Causes
+  // MostVisitedItemsChanged() to be called on |observers_|.
+  void MostVisitedItemsReceived(const history::MostVisitedURLList& data);
+
   Profile* const profile_;
+  scoped_ptr<InstantPreloader> preloader_;
+  scoped_refptr<InstantIOContext> io_context_;
 
-  // The process ids associated with Instant processes.
+  DebugEventsList debug_events_;
+
+  ObserverList<InstantServiceObserver> observers_;
+  content::NotificationRegistrar notification_registrar_;
+  PrefChangeRegistrar pref_change_registrar_;
+
+  // The process IDs associated with Instant processes.
   std::set<int> process_ids_;
 
-  content::NotificationRegistrar registrar_;
+  // Omnibox font name and size. Initialized at startup. These never change.
+  string16 omnibox_font_name_;
+  size_t omnibox_font_size_;
 
-  scoped_refptr<InstantIOContext> instant_io_context_;
+  int omnibox_start_margin_;
+
+  bool instant_pref_enabled_;
+  bool instant_enabled_;
+
+  ThemeBackgroundInfo theme_info_;
+
+  std::vector<MostVisitedItem> most_visited_items_;
 
   DISALLOW_COPY_AND_ASSIGN(InstantService);
 };
 
 #endif  // CHROME_BROWSER_INSTANT_INSTANT_SERVICE_H_