Revert of Ensure RenderFrameHost & NavigationHandle are not destroyed during commit

content/browser/frame_host/navigation_handle_impl.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 "content/browser/frame_host/navigation_handle_impl.h"
 
 #include <utility>
 
 #include "content/browser/frame_host/frame_tree_node.h"
 #include "content/browser/frame_host/navigator.h"
@@ skipping 47 matching lines @@
       render_frame_host_(nullptr),
       is_same_page_(false),
       is_synchronous_(is_synchronous),
       is_srcdoc_(is_srcdoc),
       was_redirected_(false),
       state_(INITIAL),
       is_transferring_(false),
       frame_tree_node_(frame_tree_node),
       next_index_(0),
       navigation_start_(navigation_start),
-      pending_nav_entry_id_(pending_nav_entry_id),
-      is_in_commit_(false) {
+      pending_nav_entry_id_(pending_nav_entry_id) {
   DCHECK(!navigation_start.is_null());
   GetDelegate()->DidStartNavigation(this);
 }
 
 NavigationHandleImpl::~NavigationHandleImpl() {
   GetDelegate()->DidFinishNavigation(this);
 
-  CHECK(!is_in_commit_);
-
   // Cancel the navigation on the IO thread if the NavigationHandle is being
   // destroyed in the middle of the NavigationThrottles checks.
   if (!IsBrowserSideNavigationEnabled() && !complete_callback_.is_null())
     RunCompleteCallback(NavigationThrottle::CANCEL_AND_IGNORE);
 }
 
 NavigatorDelegate* NavigationHandleImpl::GetDelegate() const {
   return frame_tree_node_->navigator()->GetDelegate();
 }
 
@@ skipping 396 matching lines @@
   complete_callback_.Reset();
 
   if (!callback.is_null())
     callback.Run(result);
 
   // No code after running the callback, as it might have resulted in our
   // destruction.
 }
 
 }  // namespace content