[Search] Store and recall search terms using NavigationEntry to improve search term extraction

content/public/browser/navigation_entry.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 CONTENT_PUBLIC_BROWSER_NAVIGATION_ENTRY_H_
 #define CONTENT_PUBLIC_BROWSER_NAVIGATION_ENTRY_H_
 
 #include <string>
 
 #include "base/memory/ref_counted_memory.h"
@@ skipping 170 matching lines @@
   // Used to specify if this entry should be able to access local file://
   // resources.
   virtual void SetCanLoadLocalResources(bool allow) = 0;
   virtual bool GetCanLoadLocalResources() const = 0;
 
   // Used to specify which frame to navigate. If empty, the main frame is
   // navigated. This is currently not persisted in session restore, because it
   // is currently only used in tests.
   virtual void SetFrameToNavigate(const std::string& frame_name) = 0;
   virtual const std::string& GetFrameToNavigate() const = 0;
+
+  // Set extra data on this NavigationEntry according to the specified |key|.
+  // This data is not persisted by default.
+  virtual void SetExtraData(const std::string& key, const string16& data) = 0;
+  // If present, fills the |data| present at the specified |key|.
+  virtual bool GetExtraData(const std::string& key, string16* data) const = 0;
+  // Removes the data at the specified |key|.
+  virtual void ClearExtraData(const std::string& key) = 0;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_NAVIGATION_ENTRY_H_