[DRAFT] Create RenderFrameHostManager.

content/browser/frame_host/render_frame_host_impl.h

Index: content/browser/frame_host/render_frame_host_impl.h
diff --git a/content/browser/frame_host/render_frame_host_impl.h b/content/browser/frame_host/render_frame_host_impl.h
index dbe8972e2ac3a120d554c8a24fde378d49be2942..4819c520563db7d7ef2cfea2c100ac1d02768710 100644
--- a/content/browser/frame_host/render_frame_host_impl.h
+++ b/content/browser/frame_host/render_frame_host_impl.h
@@ -15,6 +15,7 @@ class GURL;
 namespace content {
 
 class FrameTree;
+class FrameTreeNode;
 class RenderProcessHost;
 class RenderViewHostImpl;
 
@@ -27,6 +28,7 @@ class CONTENT_EXPORT RenderFrameHostImpl : public RenderFrameHost {
   // into WebContentsObserver::FrameDetached for now.
   RenderFrameHostImpl(RenderViewHostImpl* render_view_host,
                       FrameTree* frame_tree,
+                      FrameTreeNode* frame_tree_node,
                       int routing_id,
                       bool is_swapped_out);
   virtual ~RenderFrameHostImpl();
@@ -49,6 +51,18 @@ class CONTENT_EXPORT RenderFrameHostImpl : public RenderFrameHost {
     return render_view_host_;
   }
 
+  // TODO(creis): Think about where this API belongs.
+  bool is_main_frame() const;
+
+  // Hack to get this subframe to swap out, without yet moving over all the
+  // state and machinery from RenderViewHost.
+  void SwapOut();
+  void OnSwappedOut(bool timed_out);
+  bool is_swapped_out() { return is_swapped_out_; }
+  void set_swapped_out(bool is_swapped_out) {
+    is_swapped_out_ = is_swapped_out;
+  }
+
  private:
   // IPC Message handlers.
   void OnDetach(int64 parent_frame_id, int64 frame_id);
@@ -56,16 +70,21 @@ class CONTENT_EXPORT RenderFrameHostImpl : public RenderFrameHost {
                                          int64 parent_frame_id,
                                          bool main_frame,
                                          const GURL& url);
+  void OnSwapOutACK();
 
-  bool is_swapped_out() { return is_swapped_out_; }
-
-  // TODO(nasko): This should be removed and replaced by RenderProcessHost.
-  RenderViewHostImpl* render_view_host_;  // Not owned.
+  // For now, RenderFrameHosts indirectly keep RenderViewHosts alive via the
+  // refcount on FrameTree.  This allows each RenderFrameHostManager to just
+  // care about RenderFrameHosts, while ensuring we have a RenderViewHost for
+  // each RenderFrameHost.
+  // TODO(creis): RenderViewHost will eventually go away and be replaced with
+  // some form of page context.
+  RenderViewHostImpl* render_view_host_;
 
   // Reference to the whole frame tree that this RenderFrameHost belongs too.
   // Allows this RenderFrameHost to add and remove nodes in response to
   // messages from the renderer requesting DOM manipulation.
   FrameTree* frame_tree_;
+  FrameTreeNode* frame_tree_node_;
   int routing_id_;
   bool is_swapped_out_;