Add NavigationEntryImpl::TreeNode for tracking FrameNavigationEntries.

content/browser/frame_host/navigation_entry_impl.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 CONTENT_BROWSER_FRAME_HOST_NAVIGATION_ENTRY_IMPL_H_
 #define CONTENT_BROWSER_FRAME_HOST_NAVIGATION_ENTRY_IMPL_H_
 
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/time/time.h"
 #include "content/browser/frame_host/frame_navigation_entry.h"
 #include "content/browser/site_instance_impl.h"
 #include "content/common/frame_message_enums.h"
 #include "content/public/browser/favicon_status.h"
 #include "content/public/browser/global_request_id.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/common/page_state.h"
 #include "content/public/common/ssl_status.h"
 
 namespace content {
 class NavigationControllerImpl;
 struct CommitNavigationParams;
 struct CommonNavigationParams;
 struct HistoryNavigationParams;
 struct StartNavigationParams;
 
 class CONTENT_EXPORT NavigationEntryImpl
     : public NON_EXPORTED_BASE(NavigationEntry) {
  public:
+  // Represents a tree of FrameNavigationEntries that make up this joint session
+  // history item.  The tree currently only tracks the main frame.
+  // TODO(creis): Populate the tree with subframe entries in --site-per-process.
+  struct TreeNode {
+    TreeNode(FrameNavigationEntry* frame_entry);
+    ~TreeNode();
+
+    // Returns a deep copy of the tree with copies of each node's
+    // FrameNavigationEntries.  We do not yet share FrameNavigationEntries
+    // across trees.
+    // TODO(creis): For --site-per-process, share FrameNavigationEntries between
+    // NavigationEntries of the same tab.
+    TreeNode* Clone() const;
+
+    // Ref counted pointer that keeps the FrameNavigationEntry alive as long as
+    // it is needed by this node's NavigationEntry.
+    scoped_refptr<FrameNavigationEntry> frame_entry;
+  };
+
   static NavigationEntryImpl* FromNavigationEntry(NavigationEntry* entry);
 
   // The value of bindings() before it is set during commit.
   static int kInvalidBindings;
 
   NavigationEntryImpl();
   NavigationEntryImpl(SiteInstanceImpl* instance,
                       int page_id,
                       const GURL& url,
                       const Referrer& referrer,
@@ skipping 74 matching lines @@
   }
 
   // The SiteInstance represents which pages must share processes. This is a
   // reference counted pointer to a shared SiteInstance.
   //
   // Note that the SiteInstance should usually not be changed after it is set,
   // but this may happen if the NavigationEntry was cloned and needs to use a
   // different SiteInstance.
   void set_site_instance(SiteInstanceImpl* site_instance);
   SiteInstanceImpl* site_instance() const {
-    return frame_entry_.site_instance();
+    return frame_tree_->frame_entry->site_instance();
   }
 
   // The |source_site_instance| is used to identify the SiteInstance of the
   // frame that initiated the navigation.
   void set_source_site_instance(SiteInstanceImpl* source_site_instance);
   SiteInstanceImpl* source_site_instance() const {
     return source_site_instance_.get();
   }
 
   // Remember the set of bindings granted to this NavigationEntry at the time
@@ skipping 129 matching lines @@
 
  private:
   // WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
   // Session/Tab restore save portions of this class so that it can be recreated
   // later. If you add a new field that needs to be persisted you'll have to
   // update SessionService/TabRestoreService and Android WebView
   // state_serializer.cc appropriately.
   // For all new fields, update |Clone| and possibly |ResetForCommit|.
   // WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
 
-  // The FrameNavigationEntry for the main frame.
-  // TODO(creis): Make this a tree with nodes for each frame in the page.
-  FrameNavigationEntry frame_entry_;
+  // Tree of FrameNavigationEntries, one for each frame on the page.
+  // TODO(creis): Once FrameNavigationEntries can be shared across multiple
+  // NavigationEntries, we will need to update Session/Tab restore.  For now,
+  // each NavigationEntry's tree has its own unshared FrameNavigationEntries.
+  scoped_ptr<TreeNode> frame_tree_;
 
   // See the accessors above for descriptions.
   int unique_id_;
   // TODO(creis): Persist bindings_. http://crbug.com/173672.
   int bindings_;
   PageType page_type_;
   GURL virtual_url_;
   bool update_virtual_url_with_url_;
   base::string16 title_;
   FaviconStatus favicon_;
@@ skipping 105 matching lines @@
   // persisted, unless specific data is taken out/put back in at save/restore
   // time (see TabNavigation for an example of this).
   std::map<std::string, base::string16> extra_data_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationEntryImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_NAVIGATION_ENTRY_IMPL_H_