Update ThreatDOMDetails to be able to collect non-resource HTML Elements based on their attributes.

chrome/browser/safe_browsing/threat_details.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.
 //
 // Implementation of the ThreatDetails class.
 
 #include "chrome/browser/safe_browsing/threat_details.h"
 
 #include <stddef.h>
 #include <stdint.h>
@@ skipping 478 matching lines @@
   if (frame_url.is_empty()) {
     ambiguous_dom_ = true;
   }
 
   // Add the urls from the DOM to |resources_|. The renderer could be sending
   // bogus messages, so limit the number of nodes we accept.
   // Also update |elements_| with the DOM structure.
   for (size_t i = 0; i < params.size() && i < kMaxDomNodes; ++i) {
     SafeBrowsingHostMsg_ThreatDOMDetails_Node node = params[i];
     DVLOG(1) << node.url << ", " << node.tag_name << ", " << node.parent;
-    ClientSafeBrowsingReportRequest::Resource* resource =
-        AddUrl(node.url, node.parent, node.tag_name, &(node.children));
+    ClientSafeBrowsingReportRequest::Resource* resource = nullptr;
+    if (!node.url.is_empty()) {
+      resource = AddUrl(node.url, node.parent, node.tag_name, &(node.children));
+    }
     if (!node.tag_name.empty()) {

[Nathan Parker, 2017/02/27 23:00:36]

When would there a URL but no tag name? Maybe I'm misunderstanding tag name.

[lpz, 2017/02/28 22:53:28]

The last Node in each IPC is a "summary" node whose URL is the render frame's
document URL and its children are a flat list of all resources in the frame. It
never has a tag name.
Added a comment.

       AddDomElement(frame_tree_node_id, frame_url.spec(), node.node_id,
                     node.tag_name, node.parent_node_id, resource);
     }
   }
 }
 
 // Called from the SB Service on the IO thread, after the user has
 // closed the tab, or clicked proceed or goback.  Since the user needs
 // to take an action, we expect this to be called after
 // OnReceivedThreatDOMDetails in most cases. If not, we don't include
@@ skipping 69 matching lines @@
   // Send the report, using the SafeBrowsingService.
   std::string serialized;
   if (!report_->SerializeToString(&serialized)) {
     DLOG(ERROR) << "Unable to serialize the threat report.";
     return;
   }
   ui_manager_->SendSerializedThreatDetails(serialized);
 }
 
 }  // namespace safe_browsing