Make <webview> use out-of-process iframe architecture.

content/browser/frame_host/render_frame_host_manager.h

Index: content/browser/frame_host/render_frame_host_manager.h
diff --git a/content/browser/frame_host/render_frame_host_manager.h b/content/browser/frame_host/render_frame_host_manager.h
index 89eeef69f9d549dc85a644eb8021a57176ce91d2..d3d79387766c4133a502a3999f397243ffcc1fbf 100644
--- a/content/browser/frame_host/render_frame_host_manager.h
+++ b/content/browser/frame_host/render_frame_host_manager.h
@@ -173,6 +173,8 @@ class CONTENT_EXPORT RenderFrameHostManager : public NotificationObserver {
     // hidden state.
     virtual bool IsHidden() = 0;
 
+    virtual int64 GetParentFrameTreeNodeID() = 0;

[Charlie Reis, 2015/04/08 23:42:11]

This needs a better name.  A RFHM belongs to a FrameTreeNode, which may have a
parent FrameTreeNode in the current WebContents.  In contrast, this method
normally returns -1 unless the WebContents itself has a parent WebContents.

Maybe something like GetEmbedderFrameTreeNodeID()?

[lazyboy, 2015/04/14 01:38:03]

Changed to GetEmbedderFrameTreeNodeID(), added doc.

+
    protected:
     virtual ~Delegate() {}
   };
@@ -219,6 +221,7 @@ class CONTENT_EXPORT RenderFrameHostManager : public NotificationObserver {
   RenderWidgetHostView* GetRenderWidgetHostView() const;
 
   RenderFrameProxyHost* GetProxyToParent();
+  RenderFrameProxyHost* GetProxyToEmbedder();
 
   // Returns the pending RenderFrameHost, or NULL if there is no pending one.
   RenderFrameHostImpl* pending_frame_host() const {
@@ -415,6 +418,16 @@ class CONTENT_EXPORT RenderFrameHostManager : public NotificationObserver {
                                    RenderViewHostImpl* render_view_host,
                                    SiteInstance* instance);
 
+  // Creates a proxy pointing to embedder process inside a guest RFHM.

[Charlie Reis, 2015/04/08 23:42:11]

Terminology: "proxy for frame X in process Y"
Pointing to a process doesn't really make sense; instead, the proxy lives in the
process and represents a frame rendered elsewhere.

[lazyboy, 2015/04/14 01:38:03]

Thanks for the terminology.
Changed.

+  // This proxy is used to swap out the initial guest frame in embedder.
+  // Returns the routing id of the created proxy.
+  int CreateEmbedderProxy(SiteInstance* embedder_site_instance,
+                          int* swapped_out_render_view_routing_id);

[Charlie Reis, 2015/04/08 23:42:11]

Let's avoid having a mix of return parameters and out parameters if we can.

[lazyboy, 2015/04/14 01:38:03]

I've changed both to out parameters.

+
+  // Replaces initial guest frame in embedder with the proxy that has routing
+  // id |proxy_to_embedder_routing_id|.
+  void ReplaceWithGuestProxy(int proxy_to_embedder_routing_id);
+
  private:
   friend class NavigatorTestWithBrowserSideNavigation;
   friend class RenderFrameHostManagerTest;