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

content/browser/web_contents/web_contents_impl.cc

 // Copyright (c) 2012 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 "content/browser/web_contents/web_contents_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
@@ skipping 74 matching lines @@
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/render_widget_host_iterator.h"
 #include "content/public/browser/resource_request_details.h"
 #include "content/public/browser/screen_orientation_dispatcher_host.h"
 #include "content/public/browser/security_style_explanations.h"
 #include "content/public/browser/storage_partition.h"
 #include "content/public/browser/user_metrics.h"
 #include "content/public/browser/web_contents_delegate.h"
 #include "content/public/browser/web_contents_observer.h"
+#include "content/public/browser/web_contents_source.h"
 #include "content/public/common/bindings_policy.h"
 #include "content/public/common/browser_plugin_guest_mode.h"
 #include "content/public/common/content_constants.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/page_zoom.h"
 #include "content/public/common/result_codes.h"
 #include "content/public/common/security_style.h"
 #include "content/public/common/url_constants.h"
 #include "content/public/common/url_utils.h"
 #include "content/public/common/web_preferences.h"
@@ skipping 1671 matching lines @@
     create_params.initially_hidden = true;
   create_params.renderer_initiated_creation =
       main_frame_route_id != MSG_ROUTING_NONE;
 
   WebContentsImpl* new_contents = NULL;
   if (!is_guest) {
     create_params.context = view_->GetNativeView();
     create_params.initial_size = GetContainerBounds().size();
     new_contents = static_cast<WebContentsImpl*>(
         WebContents::Create(create_params));
+    WebContentsSource::CreateForWebContentsAndLocation(new_contents, FROM_HERE);
   }  else {
     new_contents = GetBrowserPluginGuest()->CreateNewGuestWindow(create_params);
   }
   new_contents->GetController().SetSessionStorageNamespace(
       partition_id,
       session_storage_namespace);
 
   // If the new frame has a name, make sure any SiteInstances that can find
   // this named frame have proxies for it.  Must be called after
   // SetSessionStorageNamespace, since this calls CreateRenderView, which uses
@@ skipping 2941 matching lines @@
   return NULL;
 }
 
 void WebContentsImpl::SetForceDisableOverscrollContent(bool force_disable) {
   force_disable_overscroll_content_ = force_disable;
   if (view_)
     view_->SetOverscrollControllerEnabled(CanOverscrollContent());
 }
 
 }  // namespace content