Integrated test with the actual QuotaManager and PathManager.

webkit/fileapi/file_system_test_helper.cc

Index: webkit/fileapi/file_system_test_helper.cc
diff --git a/webkit/fileapi/file_system_test_helper.cc b/webkit/fileapi/file_system_test_helper.cc
index c51fe7f9607e3f05f1934e59d46891da54657a49..b7813fae530275694dbdee49999acde2492b7167 100644
--- a/webkit/fileapi/file_system_test_helper.cc
+++ b/webkit/fileapi/file_system_test_helper.cc
@@ -125,6 +125,8 @@ void FileSystemTestOriginHelper::SetUp(
   // how much the size of the origin directory has grown.
   initial_usage_size_ = file_util::ComputeDirectorySize(
       GetOriginRootPath());
+
+  FileSystemUsageCache::UpdateUsage(usage_cache_path, initial_usage_size_);
 }
 
 void FileSystemTestOriginHelper::TearDown() {
@@ -162,7 +164,8 @@ FilePath FileSystemTestOriginHelper::GetUsageCachePath() const {
 }
 
 int64 FileSystemTestOriginHelper::GetCachedOriginUsage() const {
-  return FileSystemUsageCache::GetUsage(GetUsageCachePath());
+  return FileSystemUsageCache::GetUsage(GetUsageCachePath()) -
+      initial_usage_size_;
 }
 
 int64 FileSystemTestOriginHelper::ComputeCurrentOriginUsage() const {