Adds a new checkbox for backup and restore in opt-in flow.

chrome/browser/chromeos/arc/arc_support_host.cc

Index: chrome/browser/chromeos/arc/arc_support_host.cc
diff --git a/chrome/browser/chromeos/arc/arc_support_host.cc b/chrome/browser/chromeos/arc/arc_support_host.cc
index 3713eb058dab9ea26329320fbb9e032a40d6dcb9..bdc78c67af0dba74adf47f1b12f14cf0d9d9d446 100644
--- a/chrome/browser/chromeos/arc/arc_support_host.cc
+++ b/chrome/browser/chromeos/arc/arc_support_host.cc
@@ -19,6 +19,7 @@
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/ash/multi_user/multi_user_util.h"
 #include "chrome/browser/ui/browser_commands.h"
+#include "chrome/common/pref_names.h"
 #include "chrome/grit/generated_resources.h"
 #include "components/metrics/metrics_pref_names.h"
 #include "components/prefs/pref_service.h"
@@ -28,13 +29,15 @@
 
 namespace {
 const char kAction[] = "action";
-const char kCode[] = "code";
+const char kBackupRestoreEnabled[] = "backupRestoreEnabled";
 const char kCanEnable[] = "canEnable";
-const char kStatus[] = "status";
+const char kCode[] = "code";
 const char kData[] = "data";
 const char kDeviceId[] = "deviceId";
+const char kEnabled[] = "enabled";
 const char kOn[] = "on";
 const char kPage[] = "page";
+const char kStatus[] = "status";
 const char kText[] = "text";
 const char kActionInitialize[] = "initialize";
 const char kActionSetMetricsMode[] = "setMetricsMode";
@@ -43,6 +46,7 @@ const char kActionCancelAuthCode[] = "cancelAuthCode";
 const char kActionSetAuthCode[] = "setAuthCode";
 const char kActionEnableMetrics[] = "enableMetrics";
 const char kActionSendFeedback[] = "sendFeedback";
+const char kActionSetBackupRestore[] = "setBackupRestore";
 const char kActionCloseUI[] = "closeUI";
 const char kActionShowPage[] = "showPage";
 }  // namespace
@@ -98,7 +102,6 @@ void ArcSupportHost::Start(Client* client) {
 
 void ArcSupportHost::Initialize() {
   DCHECK(client_);
-
   std::unique_ptr<base::DictionaryValue> localized_strings(
       new base::DictionaryValue());
   base::string16 device_name = ash::GetChromeOSDeviceName();
@@ -133,14 +136,23 @@ void ArcSupportHost::Initialize() {
   localized_strings->SetString(
       "termsOfService",
       l10n_util::GetStringUTF16(IDS_ARC_OPT_IN_DIALOG_TERMS_OF_SERVICE));
+  localized_strings->SetString(
+      "textBackupRestore",
+      l10n_util::GetStringUTF16(IDS_ARC_OPT_IN_DIALOG_BACKUP_RESTORE));
 
   const std::string& app_locale = g_browser_process->GetApplicationLocale();
   const std::string& country_code = base::CountryCodeForCurrentTimezone();
   localized_strings->SetString("countryCode", country_code);
 
-  webui::SetLoadTimeDataDefaults(app_locale, localized_strings.get());
 
   arc::ArcAuthService* arc_auth_service = arc::ArcAuthService::Get();
+
+  localized_strings->SetBoolean(

[elijahtaylor1, 2016/06/30 01:59:06]

We want the default to be checked, and set the pref based on the result of the
checkbox when the user agrees.  We don't care about the previous state of this
pref here (or its default state).

This could be initialized in javascript and you wouldn't need
kBackupRestoreEnabled and communication of this to the support extension.

[malaykeshav, 2016/06/30 02:46:19]

What about the case where the opt-in fails. Do we not save the state when the
user retries?

[elijahtaylor1, 2016/06/30 04:52:34]

That's a good point, and I do think it's the right thing to preserve that
selection.  But we still need to change this so the default is true instead of
false, which I think is the default for an unset boolean pref.

[malaykeshav, 2016/06/30 18:25:46]

This is already set when defining the boolean preference value here:
https://codereview.chromium.org/2104893003/diff/140001/chrome/browser/chromeo...

[khmel, 2016/06/30 18:30:11]

BTW, if OptIn fails, 'Get Started' page is not shown, retry starts from LSO page

[xiyuan, 2016/06/30 18:34:22]

What about user disables ARC then re-enables it in settings? Think we should
always get the pref value to init the opt-in page to be correct.

[malaykeshav, 2016/06/30 18:50:59]

The user's choice persists across the disable-renable

[khmel, 2016/06/30 19:00:43]

I also still think that 
 pref_change_registrar_.Add(prefs::kArcBackupRestoreEnabled) might make sense

+      kBackupRestoreEnabled,
+      arc_auth_service->profile()->GetPrefs()->GetBoolean(
+          prefs::kArcBackupRestoreEnabled));
+
+  webui::SetLoadTimeDataDefaults(app_locale, localized_strings.get());
   DCHECK(arc_auth_service);
   const std::string device_id = user_manager::known_user::GetDeviceId(
       multi_user_util::GetAccountIdFromProfile(arc_auth_service->profile()));
@@ -215,8 +227,13 @@ void ArcSupportHost::OnOptInUIShowPage(arc::ArcAuthService::UIPage page,
   client_->PostMessageFromNativeHost(response_string);
 }
 
-void ArcSupportHost::EnableMetrics() {
-  InitiateMetricsReportingChange(true, OnMetricsReportingCallbackType());
+void ArcSupportHost::EnableMetrics(bool is_enabled) {
+  InitiateMetricsReportingChange(is_enabled, OnMetricsReportingCallbackType());
+}
+
+void ArcSupportHost::EnableBackupRestore(bool is_enabled) {
+  PrefService* pref_service = arc::ArcAuthService::Get()->profile()->GetPrefs();
+  pref_service->SetBoolean(prefs::kArcBackupRestoreEnabled, is_enabled);
 }
 
 void ArcSupportHost::OnMessage(const std::string& request_string) {
@@ -249,9 +266,21 @@ void ArcSupportHost::OnMessage(const std::string& request_string) {
   } else if (action == kActionCancelAuthCode) {
     arc_auth_service->CancelAuthCode();
   } else if (action == kActionEnableMetrics) {
-    EnableMetrics();
+    bool is_enabled;
+    if (!request->GetBoolean(kEnabled, &is_enabled)) {
+      NOTREACHED();
+      return;
+    }
+    EnableMetrics(is_enabled);
   } else if (action == kActionSendFeedback) {
     chrome::OpenFeedbackDialog(nullptr);
+  } else if (action == kActionSetBackupRestore) {
+    bool is_enabled;
+    if (!request->GetBoolean(kEnabled, &is_enabled)) {
+      NOTREACHED();
+      return;
+    }
+    EnableBackupRestore(is_enabled);
   } else {
     NOTREACHED();
   }