Refactor and fix feedback

chrome/browser/feedback/proto/dom.proto

 // Copyright 2009 Google Inc. All Rights Reserved.
 // Author: micapolos@google.com (Michal Pociecha-Los)
 //
 // Messages containing DOM data captured from the browser.
 // It includes the structure of the HTML document and Navigator data.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
@@ skipping 80 matching lines @@
 // A path in the HTML document between two elements, which are in the
 // ancestor-descendant relationship.
 message HtmlPath {
 
   // Ordered list of zero-based indices.
   // Empty path selects root element.
   // Non-negative index N selects (N+1)-th child.
   // Index -1 selects root element from frame content document.
   repeated int32 index = 1;
 };