Don't remove DistillabilityService on RenderFrameHost switch

components/dom_distiller/content/browser/distillability_driver.cc

 // Copyright 2015 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.
 
 #include "components/dom_distiller/content/browser/distillability_driver.h"
 
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
@@ skipping 67 matching lines @@
     content::RenderFrameHost* old_host,
     content::RenderFrameHost* new_host) {
   // This method is invoked if any of the active RenderFrameHosts are swapped.
   // Only add the mojo service to the main frame host.
   if (!web_contents() || web_contents()->GetMainFrame() != new_host) return;
 
   // If the RenderFrameHost changes (this will happen if the user navigates to
   // or from a native page), the service needs to be attached to that host.
   mojo_needs_setup_ = true;
   SetupMojoService(new_host);
-  // Clean up the service on the old host if possible.
-  if (!old_host || !old_host->GetInterfaceRegistry()) return;
-  old_host->GetInterfaceRegistry()
-      ->RemoveInterface<mojom::DistillabilityService>();
 }
 
 void DistillabilityDriver::DidStartProvisionalLoadForFrame(
     content::RenderFrameHost* render_frame_host, const GURL& validated_url,
     bool is_error_page, bool is_iframe_srcdoc) {
   SetupMojoService(render_frame_host);
 }
 
 void DistillabilityDriver::SetupMojoService(
     content::RenderFrameHost* frame_host) {
   if (!frame_host || !frame_host->GetInterfaceRegistry()
       || !mojo_needs_setup_) {
     return;
   }
 
   frame_host->GetInterfaceRegistry()->AddInterface(
       base::Bind(&DistillabilityDriver::CreateDistillabilityService,
           weak_factory_.GetWeakPtr()));
   mojo_needs_setup_ = false;
 }
 
 }  // namespace dom_distiller