Linux: change protobuf default option to allow building

chrome/browser/feedback/proto/common.proto

 // 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.
 
 // 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;
 };