SyncFS: Fix when to call OnSyncIdle()

chrome/browser/sync_file_system/sync_process_runner.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/sync_file_system/sync_process_runner.h"
 
 #include "base/format_macros.h"
 #include "chrome/browser/sync_file_system/logger.h"
 #include "chrome/browser/sync_file_system/sync_file_system_service.h"
 
@@ skipping 75 matching lines @@
 }
 
 void SyncProcessRunner::ScheduleIfNotRunning() {
   if (!timer_.IsRunning())
     Schedule();
 }
 
 void SyncProcessRunner::OnChangesUpdated(
     int64 pending_changes) {
   DCHECK_GE(pending_changes, 0);
-  if (pending_changes_ != pending_changes) {
+  int64 old_pending_changes = pending_changes_;
+  pending_changes_ = pending_changes;
+  if (old_pending_changes != pending_changes) {
     if (pending_changes == 0)
       sync_service()->OnSyncIdle();
     util::Log(logging::LOG_VERBOSE, FROM_HERE,
               "[%s] pending_changes updated: %" PRId64,
               name_.c_str(), pending_changes);
   }
-  pending_changes_ = pending_changes;
   Schedule();
 }
 
 SyncServiceState SyncProcessRunner::GetServiceState() {
   return sync_service()->GetSyncServiceState();
 }
 
 void SyncProcessRunner::Finished(SyncStatusCode status) {
   DCHECK(running_);
   running_ = false;
@@ skipping 46 matching lines @@
     util::Log(logging::LOG_VERBOSE, FROM_HERE,
               "[%s] Scheduling task in %" PRId64 " secs",
               name_.c_str(), time_to_next.InSeconds());
   }
   current_delay_ = delay;
 
   timer_.Start(FROM_HERE, time_to_next, this, &SyncProcessRunner::Run);
 }
 
 }  // namespace sync_file_system