[sync] Add backup time in synced device info so that server can flag device

chrome/browser/sync/profile_sync_service.cc

Index: chrome/browser/sync/profile_sync_service.cc
diff --git a/chrome/browser/sync/profile_sync_service.cc b/chrome/browser/sync/profile_sync_service.cc
index 8d814985d9a2f9dc815376783ccf4767379a432e..2eafef7332aff882c0e3d6a727c510e9c3b99efb 100644
--- a/chrome/browser/sync/profile_sync_service.cc
+++ b/chrome/browser/sync/profile_sync_service.cc
@@ -87,6 +87,7 @@
 #include "sync/internal_api/public/sync_core_proxy.h"
 #include "sync/internal_api/public/sync_encryption_handler.h"
 #include "sync/internal_api/public/util/experiments.h"
+#include "sync/internal_api/public/util/sync_db_util.h"
 #include "sync/internal_api/public/util/sync_string_conversions.h"
 #include "sync/js/js_event_details.h"
 #include "sync/util/cryptographer.h"
@@ -680,6 +681,8 @@ void ProfileSyncService::StartUpSlowBackendComponents(
 
   if (backend_mode_ == ROLLBACK)
     ClearBrowsingDataSinceFirstSync();
+  else if (backend_mode_ == SYNC)
+    CheckSyncBackupIfNeeded();
 
   base::FilePath sync_folder = backend_mode_ == SYNC ?
       base::FilePath(kSyncDataFolderName) :
@@ -1021,6 +1024,13 @@ void ProfileSyncService::PostBackendInitialization() {
   // Never get here for backup / restore.
   DCHECK_EQ(backend_mode_, SYNC);
 
+  if (last_backup_time_) {
+    browser_sync::SyncedDeviceTracker* device_tracker =
+        backend_->GetSyncedDeviceTracker();
+    if (device_tracker)
+      device_tracker->UpdateLocalDeviceBackupTime(*last_backup_time_);
+  }
+
   if (protocol_event_observers_.might_have_observers()) {
     backend_->RequestBufferedProtocolEventsAndEnableForwarding();
   }
@@ -2553,3 +2563,41 @@ void ProfileSyncService::SetClearingBrowseringDataForTesting(
     base::Callback<void(Profile*, base::Time, base::Time)> c) {
   clear_browsing_data_ = c;
 }
+
+void ProfileSyncService::CheckSyncBackupIfNeeded() {
+  DCHECK_EQ(backend_mode_, SYNC);
+
+#if defined(OS_WIN) || defined(OS_MACOSX) || (defined(OS_LINUX) && !defined(OS_CHROMEOS))

[Nicolas Zea, 2014/06/13 22:36:41]

I wonder if it's better to pull out these platform-specific macros and just have
an #if defined(ENABLE_SYNC_BACKUP), which is defined in common.gypi for the
specified platforms. That way if we decide to enable it on e.g. mobile we don't
have to find all the places this guard exists.

See for example ENABLE_EXTENSIONS macro

[haitaol1, 2014/06/13 23:28:25]

Will do in follow-up cl.

On 2014/06/13 22:36:41, Nicolas Zea wrote:

+  // Check backup once a day.
+  if (last_synced_time_.is_null() ||
+      base::Time::Now() - last_synced_time_ >= base::TimeDelta::FromDays(1)) {
+    // If sync thread is set, need to serialize check on sync thread after
+    // closing backup DB.

[Nicolas Zea, 2014/06/13 22:36:41]

Why do we need to serialize on the sync thread in some cases? 

[haitaol1, 2014/06/13 23:28:25]

Check will fail if sync DB is still opened by backup backend.

On 2014/06/13 22:36:41, Nicolas Zea wrote:

[Nicolas Zea, 2014/06/13 23:48:52]

If the backup is running, why not have it do this work automatically and post
the result back? In that case, this CheckSyncBackupIfNeeded does nothing.

[haitaol1, 2014/06/16 17:35:28]

Backup may or may not be running at the time. If it's first time sync, it's
likely that backup is running, but not guaranteed because of startup delay or
unrecoverable error. For periodical check after first signin, backup is
definitely not running. 

On 2014/06/13 23:48:52, Nicolas Zea wrote:

+    base::TaskRunner* check_task_runner = sync_thread_ ?
+        sync_thread_->message_loop_proxy().get() :
+        profile_->GetIOTaskRunner().get();
+    check_task_runner->PostTask(
+        FROM_HERE,
+        base::Bind(syncer::CheckSyncDbLastModifiedTime,
+                   profile_->GetPath().Append(kSyncBackupDataFolderName),
+                   base::MessageLoopProxy::current(),
+                   base::Bind(&ProfileSyncService::CheckSyncBackupCallback,
+                              weak_factory_.GetWeakPtr())));
+  }
+#endif
+}
+
+void ProfileSyncService::CheckSyncBackupCallback(base::Time backup_time) {
+  last_backup_time_.reset(new base::Time(backup_time));
+
+  if (HasSyncingBackend()) {
+    browser_sync::SyncedDeviceTracker* device_tracker =
+        backend_->GetSyncedDeviceTracker();
+    if (device_tracker)
+      device_tracker->UpdateLocalDeviceBackupTime(*last_backup_time_);
+  }
+}
+
+base::Time ProfileSyncService::GetDeviceBackupTimeForTesting() const {
+  return backend_->GetSyncedDeviceTracker()->GetLocalDeviceBackupTime();
+}