Track where WebContents are created in order to better understand issue.

components/guest_view/browser/guest_view_manager.cc

 // Copyright 2014 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/guest_view/browser/guest_view_manager.h"
 
 #include "base/macros.h"
 #include "base/strings/stringprintf.h"
 #include "components/guest_view/browser/guest_view_base.h"
 #include "components/guest_view/browser/guest_view_manager_delegate.h"
 #include "components/guest_view/browser/guest_view_manager_factory.h"
 #include "components/guest_view/common/guest_view_constants.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/render_process_host.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/user_metrics.h"
 #include "content/public/browser/web_contents_observer.h"
+#include "content/public/browser/web_contents_source.h"
 #include "content/public/common/child_process_host.h"
 #include "content/public/common/result_codes.h"
 #include "content/public/common/url_constants.h"
 #include "url/gurl.h"
 
 using content::BrowserContext;
 using content::RenderProcessHost;
 using content::SiteInstance;
 using content::WebContents;
 
@@ skipping 144 matching lines @@
 content::WebContents* GuestViewManager::CreateGuestWithWebContentsParams(
     const std::string& view_type,
     content::WebContents* owner_web_contents,
     const content::WebContents::CreateParams& create_params) {
   auto guest = CreateGuestInternal(owner_web_contents, view_type);
   if (!guest)
     return nullptr;
   content::WebContents::CreateParams guest_create_params(create_params);
   guest_create_params.guest_delegate = guest;
   auto guest_web_contents = WebContents::Create(guest_create_params);
+  WebContentsSource::CreateForWebContentsAndLocation(guest_web_contents,
+                                                     FROM_HERE);
   guest->InitWithWebContents(base::DictionaryValue(), guest_web_contents);
   return guest_web_contents;
 }
 
 content::WebContents* GuestViewManager::GetGuestByInstanceID(
     int owner_process_id,
     int element_instance_id) {
   int guest_instance_id = GetGuestInstanceIDForElementID(owner_process_id,
                                                          element_instance_id);
   if (guest_instance_id == kInstanceIDNone)
@@ skipping 296 matching lines @@
 }
 
 GuestViewManager::GuestViewData::GuestViewData(
     const GuestViewCreateFunction& create_function,
     const GuestViewCleanUpFunction& cleanup_function)
     : create_function(create_function), cleanup_function(cleanup_function) {}
 
 GuestViewManager::GuestViewData::~GuestViewData() {}
 
 }  // namespace guest_view