Make Help app behaviour in Demo Mode the same as Get Help.

This means it doesn't show in the launcher, and it records the correct
metric.

Bug: b/150738188
Change-Id: I8e14ca21a68bac95f0b7dae8b8719632289089ee
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2086382Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Reviewed-by: Patti <patricialor@chromium.org>
Commit-Queue: Rachel Carpenter <carpenterr@google.com>
Cr-Commit-Position: refs/heads/master@{#747466}

ash/metrics/demo_session_metrics_recorder.cc

@@ -32,6 +32,10 @@ using DemoModeApp = DemoSessionMetricsRecorder::DemoModeApp;
 // How often to sample.
 constexpr auto kSamplePeriod = base::TimeDelta::FromSeconds(1);
 
+// Redefining chromeos::default_web_apps::kHelpAppId as ash can't depend on
+// chrome.
+constexpr char kHelpAppId[] = "nbljnnecbjbmifnoehiemkgefbnpoeak";
+
 // How many periods to wait for user activity before discarding samples.
 // This timeout is low because demo sessions tend to be very short. If we
 // recorded samples for a full minute while the device is in between uses, we
@@ -64,7 +68,7 @@ DemoModeApp GetAppFromAppId(const std::string& app_id) {
     return DemoModeApp::kBrowser;
   if (app_id == extension_misc::kFilesManagerAppId)
     return DemoModeApp::kFiles;
-  if (app_id == extension_misc::kGeniusAppId)
+  if (app_id == kHelpAppId || app_id == extension_misc::kGeniusAppId)
     return DemoModeApp::kGetHelp;
   if (app_id == extension_misc::kGoogleKeepAppId)
     return DemoModeApp::kGoogleKeep;

chrome/browser/chromeos/login/demo_mode/demo_session.cc

@@ -28,6 +28,7 @@
 #include "chrome/browser/apps/platform_apps/app_load_service.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/browser_process_platform_part.h"
+#include "chrome/browser/chromeos/extensions/default_web_app_ids.h"
 #include "chrome/browser/chromeos/file_manager/path_util.h"
 #include "chrome/browser/chromeos/login/demo_mode/demo_resources.h"
 #include "chrome/browser/chromeos/login/demo_mode/demo_setup_controller.h"
@@ -341,7 +342,8 @@ bool DemoSession::ShouldDisplayInAppLauncher(const std::string& app_id) {
     return true;
   return app_id != GetScreensaverAppId() &&
          app_id != extensions::kWebStoreAppId &&
-         app_id != extension_misc::kGeniusAppId;
+         app_id != extension_misc::kGeniusAppId &&
+         app_id != default_web_apps::kHelpAppId;
 }
 
 // static