Send the value of google_brand::GetBrand in component update checks.

components/update_client/update_checker.cc

 // Copyright 2014 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.
 
 #include "components/update_client/update_checker.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <vector>
@@ skipping 27 matching lines @@
 //    <app appid="hnimpnehoodheedghdeeijklkeaacbdc"
 //         version="0.1.2.3" installsource="ondemand">
 //      <updatecheck />
 //      <packages>
 //        <package fp="abcd" />
 //      </packages>
 //    </app>
 std::string BuildUpdateCheckRequest(const Configurator& config,
                                     const std::vector<CrxUpdateItem*>& items,
                                     const std::string& additional_attributes) {
+  const std::string brand(config.GetBrand());
   std::string app_elements;
   for (size_t i = 0; i != items.size(); ++i) {
     const CrxUpdateItem* item = items[i];
     std::string app("<app ");
     base::StringAppendF(&app, "appid=\"%s\" version=\"%s\"", item->id.c_str(),
                         item->component.version.GetString().c_str());
+    if (!brand.empty())
+      base::StringAppendF(&app, " brand=\"%s\"", brand.c_str());

[waffles, 2016/03/22 23:01:34]

Can we sanitize brand (to "^([a-zA-Z]{4})?$") before appending it like this?
IIUC, there isn't any sanitization in google_brand::GetBrand.

[Sorin Jianu, 2016/03/23 02:10:32]

Done.

     if (item->on_demand)
       base::StringAppendF(&app, " installsource=\"ondemand\"");
     base::StringAppendF(&app, ">");
     base::StringAppendF(&app, "<updatecheck />");
     if (!item->component.fingerprint.empty()) {
       base::StringAppendF(&app,
                           "<packages>"
                           "<package fp=\"%s\"/>"
                           "</packages>",
                           item->component.fingerprint.c_str());
@@ skipping 84 matching lines @@
 }
 
 }  // namespace
 
 scoped_ptr<UpdateChecker> UpdateChecker::Create(
     const scoped_refptr<Configurator>& config) {
   return scoped_ptr<UpdateChecker>(new UpdateCheckerImpl(config));
 }
 
 }  // namespace update_client