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

components/constrained_window/constrained_window_views.cc

Index: components/constrained_window/constrained_window_views.cc
diff --git a/components/constrained_window/constrained_window_views.cc b/components/constrained_window/constrained_window_views.cc
index 3bf1dfc386b7974af9295047db567239d677f841..5ae6cd7776da6ae7eb24433ddda5d07c808fa9bd 100644
--- a/components/constrained_window/constrained_window_views.cc
+++ b/components/constrained_window/constrained_window_views.cc
@@ -6,7 +6,6 @@
 
 #include <algorithm>
 
-#include "base/debug/alias.h"
 #include "components/constrained_window/constrained_window_views_client.h"
 #include "components/guest_view/browser/guest_view_base.h"
 #include "components/web_modal/web_contents_modal_dialog_host.h"
@@ -147,12 +146,6 @@
 
 views::Widget* CreateWebModalDialogViews(views::WidgetDelegate* dialog,
                                          content::WebContents* web_contents) {
-  // Temporary to track down http://crbug.com/538612
-  content::WebContentsDelegate* delegate = web_contents->GetDelegate();
-  base::debug::Alias(delegate);
-  CHECK(
-      web_modal::WebContentsModalDialogManager::FromWebContents(web_contents));
-
   DCHECK_EQ(ui::MODAL_TYPE_CHILD, dialog->GetModalType());
   return views::DialogDelegate::CreateDialogWidget(
       dialog, nullptr,