Disable tab syncing when history saving is disabled.

chrome/browser/sync/sessions/session_data_type_controller.cc

Index: chrome/browser/sync/sessions/session_data_type_controller.cc
diff --git a/chrome/browser/sync/sessions/session_data_type_controller.cc b/chrome/browser/sync/sessions/session_data_type_controller.cc
index 24930ad44f27ad0ac597b05c419ff48861781972..fcf6dc7dbc47456ebf66f2e4292ae5301a89745e 100644
--- a/chrome/browser/sync/sessions/session_data_type_controller.cc
+++ b/chrome/browser/sync/sessions/session_data_type_controller.cc
@@ -4,11 +4,13 @@
 
 #include "chrome/browser/sync/sessions/session_data_type_controller.h"
 
+#include "base/prefs/pref_service.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/sync/glue/chrome_report_unrecoverable_error.h"
 #include "chrome/browser/sync/glue/synced_window_delegate.h"
 #include "chrome/browser/sync/sessions/synced_window_delegates_getter.h"
+#include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_details.h"
 #include "content/public/browser/notification_service.h"
@@ -34,12 +36,17 @@ SessionDataTypeController::SessionDataTypeController(
       waiting_on_session_restore_(false),
       waiting_on_local_device_info_(false) {
   DCHECK(local_device_);
+  pref_registrar_.Init(profile->GetPrefs());
+  pref_registrar_.Add(
+      prefs::kSavingBrowserHistoryDisabled,
+      base::Bind(&SessionDataTypeController::OnSavingBrowserHistoryPrefChanged,
+                 base::Unretained(this)));
 }
 
 SessionDataTypeController::~SessionDataTypeController() {}
 
 bool SessionDataTypeController::StartModels() {
-  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   std::set<browser_sync::SyncedWindowDelegate*> window =
       synced_window_getter_->GetSyncedWindowDelegates();
   for (std::set<browser_sync::SyncedWindowDelegate*>::const_iterator i =
@@ -68,6 +75,12 @@ void SessionDataTypeController::StopModels() {
   notification_registrar_.RemoveAll();
 }
 
+bool SessionDataTypeController::ReadyForStart() const {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  return !profile_->GetPrefs()->GetBoolean(
+      prefs::kSavingBrowserHistoryDisabled);
+}
+
 bool SessionDataTypeController::IsWaiting() {
   return waiting_on_session_restore_ || waiting_on_local_device_info_;
 }
@@ -82,7 +95,7 @@ void SessionDataTypeController::Observe(
     int type,
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
-  DCHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::UI));
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK_EQ(chrome::NOTIFICATION_SESSION_RESTORE_COMPLETE, type);
   DCHECK_EQ(profile_, content::Source<Profile>(source).ptr());
   notification_registrar_.RemoveAll();
@@ -99,4 +112,21 @@ void SessionDataTypeController::OnLocalDeviceInfoInitialized() {
   MaybeCompleteLoading();
 }
 
+void SessionDataTypeController::OnSavingBrowserHistoryPrefChanged() {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  if (profile_->GetPrefs()->GetBoolean(prefs::kSavingBrowserHistoryDisabled)) {
+    // If history and tabs persistence is turned off then generate an
+    // unrecoverable error. SESSIONS won't be a registered type on the next
+    // Chrome restart.
+    if (state() != NOT_RUNNING && state() != STOPPING) {
+      syncer::SyncError error(
+          FROM_HERE,
+          syncer::SyncError::DATATYPE_POLICY_ERROR,
+          "History and tab saving is now disabled by policy.",
+          syncer::SESSIONS);
+      OnSingleDataTypeUnrecoverableError(error);
+    }
+  }
+}
+
 }  // namespace browser_sync