Add ChromeOSVersion and CustomizationId to Help app strings.

These strings are provided to the untrusted js to read and pass up to
the server.

TESTED: Manually on device to check the strings are initialised with
sensible values.

Bug: b/140151178
Change-Id: Id96a28319ed78a68d5bb635ff092c70a976754a0
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1983688Reviewed-by: Trent Apted <tapted@chromium.org>
Commit-Queue: Rachel Carpenter <carpenterr@google.com>
Cr-Commit-Position: refs/heads/master@{#728466}

chromeos/components/help_app_ui/BUILD.gn

@@ -20,6 +20,7 @@ static_library("help_app_ui") {
     "//chromeos/constants",
     "//chromeos/resources:help_app_bundle_resources",
     "//chromeos/resources:help_app_resources",
+    "//chromeos/system",
     "//content/public/browser",
     "//ui/resources:webui_resources_grd_grit",
     "//ui/webui",

chromeos/components/help_app_ui/help_app_guest_ui.cc

@@ -9,6 +9,7 @@
 #include "chromeos/grit/chromeos_help_app_bundle_resources.h"
 #include "chromeos/grit/chromeos_help_app_bundle_resources_map.h"
 #include "chromeos/grit/chromeos_help_app_resources.h"
+#include "chromeos/system/statistics_provider.h"
 #include "content/public/browser/web_ui_data_source.h"
 #include "ui/resources/grit/webui_resources.h"
 
@@ -30,6 +31,13 @@ content::WebUIDataSource* CreateHelpAppGuestDataSource() {
 
   // Add strings that can be pulled in.
   source->AddString("boardName", base::SysInfo::GetLsbReleaseBoard());
+  source->AddString("chromeOSVersion", base::SysInfo::OperatingSystemVersion());
+  std::string customization_id;
+  chromeos::system::StatisticsProvider* provider =
+      chromeos::system::StatisticsProvider::GetInstance();
+  provider->GetMachineStatistic(chromeos::system::kCustomizationIdKey,
+                                &customization_id);
+  source->AddString("customizationId", customization_id);
   source->UseStringsJs();
 
   // TODO(crbug.com/1023700): Better solution before launch.