Track frame openers in FrameTreeNodes instead of WebContents

content/browser/frame_host/frame_tree_node.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_FRAME_TREE_NODE_H_
 #define CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_NODE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 13 matching lines @@
 class NavigationRequest;
 class Navigator;
 class RenderFrameHostImpl;
 
 // When a page contains iframes, its renderer process maintains a tree structure
 // of those frames. We are mirroring this tree in the browser process. This
 // class represents a node in this tree and is a wrapper for all objects that
 // are frame-specific (as opposed to page-specific).
 class CONTENT_EXPORT FrameTreeNode {
  public:
+  class Observer {
+   public:
+    // Invoked when a FrameTreeNode is being destroyed.
+    virtual void OnFrameTreeNodeDestroyed(FrameTreeNode* node) {}
+
+    virtual ~Observer() {}
+  };
+
   // Returns the FrameTreeNode with the given global |frame_tree_node_id|,
   // regardless of which FrameTree it is in.
   static FrameTreeNode* GloballyFindByID(int frame_tree_node_id);
 
   FrameTreeNode(FrameTree* frame_tree,
                 Navigator* navigator,
                 RenderFrameHostDelegate* render_frame_delegate,
                 RenderViewHostDelegate* render_view_delegate,
                 RenderWidgetHostDelegate* render_widget_delegate,
                 RenderFrameHostManager::Delegate* manager_delegate,
                 blink::WebTreeScopeType scope,
                 const std::string& name,
                 blink::WebSandboxFlags sandbox_flags);
 
   ~FrameTreeNode();
 
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
   bool IsMainFrame() const;
 
   void AddChild(scoped_ptr<FrameTreeNode> child,
                 int process_id,
                 int frame_routing_id);
   void RemoveChild(FrameTreeNode* child);
 
   // Clears process specific-state in this node to prepare for a new process.
   void ResetForNewProcess();
 
@@ skipping 16 matching lines @@
   const std::string& frame_name() const {
     return replication_state_.name;
   }
 
   size_t child_count() const {
     return children_.size();
   }
 
   FrameTreeNode* parent() const { return parent_; }
 
+  FrameTreeNode* opener() const { return opener_; }
+
+  // Assigns a new opener for this node and, if |opener| is non-null, registers
+  // an observer that will clear this node's opener if |opener| is ever
+  // destroyed.
+  void SetOpener(FrameTreeNode* opener);
+
   FrameTreeNode* child_at(size_t index) const {
     return children_[index];
   }
 
   const GURL& current_url() const {
     return current_url_;
   }
 
   void set_current_url(const GURL& url) {
     current_url_ = url;
@@ skipping 69 matching lines @@
 
   // A RenderFrameHost in this node stopped loading.
   void DidStopLoading();
 
   // The load progress for a RenderFrameHost in this node was updated to
   // |load_progress|. This will notify the FrameTree which will in turn notify
   // the WebContents.
   void DidChangeLoadProgress(double load_progress);
 
  private:
+  class OpenerDestroyedObserver;
+
   void set_parent(FrameTreeNode* parent) { parent_ = parent; }
 
   // The next available browser-global FrameTreeNode ID.
   static int next_frame_tree_node_id_;
 
   // The FrameTree that owns us.
   FrameTree* frame_tree_;  // not owned.
 
   // The Navigator object responsible for managing navigations at this node
   // of the frame tree.
   scoped_refptr<Navigator> navigator_;
 
   // Manages creation and swapping of RenderFrameHosts for this frame.  This
   // must be declared before |children_| so that it gets deleted after them.
   // That's currently necessary so that RenderFrameHostImpl's destructor can
   // call GetProcess.
   RenderFrameHostManager render_manager_;
 
   // A browser-global identifier for the frame in the page, which stays stable
   // even if the frame does a cross-process navigation.
   const int frame_tree_node_id_;
 
   // The parent node of this frame. NULL if this node is the root or if it has
   // not yet been attached to the frame tree.
   FrameTreeNode* parent_;
 
+  // The frame that opened this frame, if any.  Will be set to null if the
+  // opener is closed, or if this frame disowns its opener by setting its
+  // window.opener to null.
+  FrameTreeNode* opener_;
+
+  // An observer that clears this node's |opener_| if the opener is destroyed.
+  // This observer is added to the |opener_|'s observer list when the |opener_|
+  // is set to a non-null node, and it is removed from that list when |opener_|
+  // changes or when this node is destroyed.

[Charlie Reis, 2015/06/09 04:38:38]

Can you add something like this?
It is also cleared if |opener_| is disowned.

[alexmos, 2015/06/09 20:13:05]

Done.

+  scoped_ptr<OpenerDestroyedObserver> opener_observer_;
+
   // The immediate children of this specific frame.
   ScopedVector<FrameTreeNode> children_;
 
   // Track the current frame's last committed URL, so we can estimate the
   // process impact of out-of-process iframes.
   // TODO(creis): Remove this when we can store subframe URLs in the
   // NavigationController.
   GURL current_url_;
 
   // Track information that needs to be replicated to processes that have
@@ skipping 11 matching lines @@
   blink::WebSandboxFlags effective_sandbox_flags_;
 
   // Used to track this node's loading progress (from 0 to 1).
   double loading_progress_;
 
   // PlzNavigate
   // Owns an ongoing NavigationRequest until it is ready to commit. It will then
   // be reset and a RenderFrameHost will be responsible for the navigation.
   scoped_ptr<NavigationRequest> navigation_request_;
 
+  // List of objects observing this FrameTreeNode.
+  base::ObserverList<Observer> observers_;
+
   DISALLOW_COPY_AND_ASSIGN(FrameTreeNode);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_FRAME_TREE_NODE_H_