Refactor and fix feedback

chrome/browser/feedback/proto/annotations.proto

 // Copyright 2009 Google Inc. All Rights Reserved.
 // Author: micapolos@google.com (Michal Pociecha-Los)
 //
 // Messages containing data about the annotations drawn on the screenshot of a 
 // web page.
 
 syntax = "proto2";
 
 option optimize_for = LITE_RUNTIME;
 
 package userfeedback;
 
 import "math.proto";
 import "dom.proto";
 
 // An annotation drawn by the user on the screenshot of a web page.
 message Annotation {
   // A rectangular area covered by this annotation on annotated image.
   // The (0, 0) coordinate is placed in the top-left corner of the image.
   // One unit corresponds to one pixel.
   required Rectangle rectangle = 1;
 
   // A snippet of text displayed inside annotated portion of a web page.
   optional string snippet = 2;
 
   // A path from root element of the document to the annotated element.
   optional HtmlPath annotatedElementPath = 3;
 };