Refactor and fix feedback

chrome/browser/userfeedback/proto/common.proto

-// Copyright 2009 Google Inc. All Rights Reserved.
-// Author: morgwai@google.com (Morgwai Kotarbinski)
-//
-// Basic messages used by all systems (extension, feedbackserver,
-// silver-bullet clustering, android etc).
-
-syntax = "proto2";
-
-option optimize_for = LITE_RUNTIME;
-
-package userfeedback;
-
-// Data present in all kinds of feedbacks, regardless of source (Web, Android,
-// other).
-message CommonData {
-  optional fixed64 gaia_id = 1;
-
-  // Description of the problem entered by user.
-  optional string description = 2;
-  optional string description_translated = 4;
-  optional string source_description_language = 5 [ default = "en" ];
-  optional string ui_language = 6 [ default = "en_US" ];
-
-  optional string user_email = 3;
-  
-  // Unique identifier of feedback report. If set than only one report
-  // with the same identifier is stored in the system.
-  // If you are not sure how to use it leave it not set.
-  optional string unique_report_identifier = 7;
-};