[DRAFT] Create RenderFrameHostManager.

content/browser/renderer_host/render_view_host_impl.h

Index: content/browser/renderer_host/render_view_host_impl.h
diff --git a/content/browser/renderer_host/render_view_host_impl.h b/content/browser/renderer_host/render_view_host_impl.h
index ec5fc1522a8bb7339111032dd3c464202d278997..61689b10aa881c8412452562456050b57148fbbc 100644
--- a/content/browser/renderer_host/render_view_host_impl.h
+++ b/content/browser/renderer_host/render_view_host_impl.h
@@ -61,7 +61,6 @@ namespace content {
 class BrowserMediaPlayerManager;
 class ChildProcessSecurityPolicyImpl;
 class PageState;
-class RenderFrameHostImpl;
 class RenderWidgetHostDelegate;
 class SessionStorageNamespace;
 class SessionStorageNamespaceImpl;
@@ -227,6 +226,21 @@ class CONTENT_EXPORT RenderViewHostImpl
     delegate_ = d;
   }
 
+  // Keep track of which RenderFrameHosts are using this RenderViewHost.  When
+  // the number drops to zero, we call Shutdown.  This cannot use frame_ids,
+  // since the RenderFrameHost may outlive the process (or may go away before
+  // the process and frame_id are created).
+  void RegisterRenderFrameHost(RenderFrameHostImpl* render_frame_host);
+  void UnregisterRenderFrameHost(RenderFrameHostImpl* render_frame_host);
+
+  // Map renderer-specific frame IDs to browser-global FrameTreeNode IDs.
+  // TODO(creis): Call Unregister.
+  void RegisterFrameID(int64 frame_id, int64 frame_tree_node_id);
+  void UnregisterFrameID(int64 frame_id);
+  bool HasFrameID(int64 frame_id) const;
+  int64 GetFrameTreeNodeID(int64 frame_id);
+  int64 GetFrameIDForTesting(int64 frame_tree_node_id) const;
+
   // Set up the RenderView child process. Virtual because it is overridden by
   // TestRenderViewHost. If the |frame_name| parameter is non-empty, it is used
   // as the name of the new top-level frame.
@@ -428,12 +442,6 @@ class CONTENT_EXPORT RenderViewHostImpl
     is_subframe_ = is_subframe;
   }
 
-  // TODO(creis): Remove this when we replace frame IDs with RenderFrameHost
-  // routing IDs.
-  int64 main_frame_id() const {
-    return main_frame_id_;
-  }
-
   // Set the opener to null in the renderer process.
   void DisownOpener();
 
@@ -481,13 +489,6 @@ class CONTENT_EXPORT RenderViewHostImpl
                         bool empty_allowed,
                         GURL* url);
 
-  // Update the FrameTree to use this RenderViewHost's main frame
-  // RenderFrameHost. Called when the RenderViewHost is committed.
-  //
-  // TODO(ajwong): Remove once RenderViewHost no longer owns the main frame
-  // RenderFrameHost.
-  void AttachToFrameTree();
-
   // The following IPC handlers are public so RenderFrameHost can call them,
   // while we transition the code to not use RenderViewHost.
   //
@@ -611,33 +612,19 @@ class CONTENT_EXPORT RenderViewHostImpl
   void OnShowPopup(const ViewHostMsg_ShowPopup_Params& params);
 #endif
 
-  // TODO(nasko): Remove this accessor once RenderFrameHost moves into the frame
-  // tree.
-  RenderFrameHostImpl* main_render_frame_host() const {
-    return main_render_frame_host_.get();
-  }
-
  private:
   friend class TestRenderViewHost;
   FRIEND_TEST_ALL_PREFIXES(RenderViewHostTest, BasicRenderFrameHost);
   FRIEND_TEST_ALL_PREFIXES(RenderViewHostTest, RoutingIdSane);
 
+  typedef base::hash_map<int64, int64> FrameIDMap;
+
   // Sets whether this RenderViewHost is swapped out in favor of another,
   // and clears any waiting state that is no longer relevant.
   void SetSwappedOut(bool is_swapped_out);
 
   bool CanAccessFilesOfPageState(const PageState& state) const;
 
-  // All RenderViewHosts must have a RenderFrameHost for its main frame.
-  // Currently the RenderFrameHost is created in lock step on construction
-  // and a pointer to the main frame is given to the FrameTreeNode
-  // when the RenderViewHost commits (see AttachToFrameTree()).
-  //
-  // TODO(ajwong): Make this reference non-owning. The root FrameTreeNode of
-  // the FrameTree should be responsible for owning the main frame's
-  // RenderFrameHost.
-  scoped_ptr<RenderFrameHostImpl> main_render_frame_host_;
-
   // Our delegate, which wants to know about changes in the RenderView.
   RenderViewHostDelegate* delegate_;
 
@@ -646,6 +633,13 @@ class CONTENT_EXPORT RenderViewHostImpl
   // over time.
   scoped_refptr<SiteInstanceImpl> instance_;
 
+  // A list of RenderFrameHosts depending on this RenderViewHost.  When the list
+  // size goes to zero, this RenderViewHost is shut down.
+  std::set<RenderFrameHostImpl*> rfh_list_;
+
+  // Map of renderer-specific frame IDs to browser-global FrameTreeNode IDs.
+  FrameIDMap frame_id_map_;
+
   // true if we are currently waiting for a response for drag context
   // information.
   bool waiting_for_drag_context_response_;
@@ -680,10 +674,9 @@ class CONTENT_EXPORT RenderViewHostImpl
   // different process from its parent page.
   bool is_subframe_;
 
-  // The frame id of the main (top level) frame. This value is set on the
-  // initial navigation of a RenderView and reset when the RenderView's
-  // process is terminated (in RenderProcessGone).
-  int64 main_frame_id_;
+  // Routing ID for the main frame's RenderFrameHost.
+  // TODO(creis): Does this need to be updated on a crash?
+  int main_frame_routing_id_;
 
   // If we were asked to RunModal, then this will hold the reply_msg that we
   // must return to the renderer to unblock it.