Add methods to NavigationHandle to allow refactoring webNavigation to use it.

content/browser/frame_host/render_frame_host_impl.cc

 // Copyright 2013 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/render_frame_host_impl.h"
 
 #include <utility>
 
 #include "base/bind.h"
 #include "base/containers/hash_tables.h"
@@ skipping 994 matching lines @@
   // navigation.
   if (navigation_handle_ &&
       navigation_handle_->GetURL() != validated_params.url) {
     navigation_handle_.reset();
   }
 
   // Synchronous renderer-initiated navigations will send a
   // DidCommitProvisionalLoad IPC without a prior DidStartProvisionalLoad
   // message.
   if (!navigation_handle_) {
-    navigation_handle_ = NavigationHandleImpl::Create(
-        validated_params.url, frame_tree_node_, base::TimeTicks::Now());
+    navigation_handle_ =
+        NavigationHandleImpl::Create(validated_params.url, frame_tree_node_,
+                                     true,   // is_synchronous

[Charlie Reis, 2016/02/04 20:46:04]

Is it safe to conclude this?  Above, we clear the NavHandle if the URL doesn't
match.  What if we're in that case for an async navigation?

[nasko, 2016/02/04 23:36:59]

Based on the comments of the two blocks, it seems that we can only get here for
synchronous navigations. The block resetting the navigation_handle_ is explicit
that it is for cases of sync navigation interrupting an ongoing one. It must be
the case, otherwise we would've gotten DidStartProvisionalLoad, which will
replace the NavigationHandle with a new one and the URLs would match.

[Charlie Reis, 2016/02/05 18:09:40]

Acknowledged.

+                                     false,  // is_srcdoc

[Charlie Reis, 2016/02/04 20:46:04]

Is it possible for srcdoc to come through this path, or is it necessarily not
synchronous?

[nasko, 2016/02/04 23:36:59]

I don't think srcdoc is synchronous. We do get DidStartProvisionalLoad for
those.

[Charlie Reis, 2016/02/05 18:09:41]

Ok, thanks.

+                                     base::TimeTicks::Now());
   }
 
   accessibility_reset_count_ = 0;
   frame_tree_node()->navigator()->DidNavigate(this, validated_params);
 
   // For a top-level frame, there are potential security concerns associated
   // with displaying graphics from a previously loaded page after the URL in
   // the omnibar has been changed. It is unappealing to clear the page
   // immediately, but if the renderer is taking a long time to issue any
   // compositor output (possibly because of script deliberately creating this
@@ skipping 1523 matching lines @@
   *dst = src;
 
   if (src.routing_id != -1)
     dst->tree_id = RoutingIDToAXTreeID(src.routing_id);
 
   if (src.parent_routing_id != -1)
     dst->parent_tree_id = RoutingIDToAXTreeID(src.parent_routing_id);
 }
 
 }  // namespace content