Create a new RenderFrameHost per child frame when --site-per-process is enabled.

content/browser/renderer_host/frame_tree_node.h

Index: content/browser/renderer_host/frame_tree_node.h
diff --git a/content/browser/web_contents/frame_tree_node.h b/content/browser/renderer_host/frame_tree_node.h
similarity index 71%
rename from content/browser/web_contents/frame_tree_node.h
rename to content/browser/renderer_host/frame_tree_node.h
index 76d2194d5c4f09116286306a656f04b2fc2a9b7a..517ec303e8dda540391cb53bbb69cb0d49bba88b 100644
--- a/content/browser/web_contents/frame_tree_node.h
+++ b/content/browser/renderer_host/frame_tree_node.h
@@ -8,25 +8,38 @@
 #include <string>
 
 #include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "content/common/content_export.h"
 #include "url/gurl.h"
 
 namespace content {
 
+class RenderFrameHostImpl;
+
 // Any page that contains iframes has a tree structure of the frames in the
 // renderer process. 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:
-  FrameTreeNode(int64 frame_id, const std::string& name);
+  static const int64 kInvalidFrameId = -1;
+
+  FrameTreeNode(int64 frame_id, const std::string& name,
+                scoped_ptr<RenderFrameHostImpl> render_frame_host);
   ~FrameTreeNode();
 
-  // This method takes ownership of the child pointer.
-  void AddChild(FrameTreeNode* child);
+  void AddChild(scoped_ptr<FrameTreeNode> child);
   void RemoveChild(int64 child_id);
 
+  scoped_ptr<RenderFrameHostImpl> ResetRenderFrameHost(

[Charlie Reis, 2013/09/11 22:25:04]

Why Reset rather than Swap or Set?

[awong, 2013/09/21 01:19:56]

Since it destroys the children, it's not just a set. I'll rename the function.

+      scoped_ptr<RenderFrameHostImpl> new_render_frame_host);
+
+  void set_frame_id(int64 frame_id) {
+    DCHECK_EQ(frame_id_, kInvalidFrameId);
+    frame_id_ = frame_id;
+  }
+
   int64 frame_id() const {
     return frame_id_;
   }
@@ -51,6 +64,10 @@ class CONTENT_EXPORT FrameTreeNode {
     current_url_ = url;
   }
 
+  RenderFrameHostImpl* render_frame_host() const {
+    return render_frame_host_.get();
+  }
+
  private:
   // The unique identifier for the frame in the page.
   int64 frame_id_;
@@ -62,6 +79,10 @@ class CONTENT_EXPORT FrameTreeNode {
   // The immediate children of this specific frame.
   ScopedVector<FrameTreeNode> children_;
 
+  // The active RenderFrameHost for this frame.
+  // TODO(ajwong): Replace with RenderFrameHostManager.
+  scoped_ptr<RenderFrameHostImpl> render_frame_host_;
+
   // 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