Change {Obfuscated|Local}FileSystemFileUtil non-Singleton to take an underlying *FileUtil.

chrome/browser/extensions/extension_file_browser_private_api.cc

Index: chrome/browser/extensions/extension_file_browser_private_api.cc
diff --git a/chrome/browser/extensions/extension_file_browser_private_api.cc b/chrome/browser/extensions/extension_file_browser_private_api.cc
index b0ad30426377c5d836cf77e7856cf9518a14eab6..43d7eb914ab81f612e3f221f241f7117e5feea12 100644
--- a/chrome/browser/extensions/extension_file_browser_private_api.cc
+++ b/chrome/browser/extensions/extension_file_browser_private_api.cc
@@ -46,6 +46,7 @@
 #include "webkit/fileapi/file_system_util.h"
 #include "webkit/fileapi/file_system_file_util.h"
 #include "webkit/fileapi/local_file_system_file_util.h"
+#include "webkit/fileapi/quota_file_util.h"
 #include "ui/base/l10n/l10n_util.h"
 
 #ifdef OS_CHROMEOS
@@ -542,7 +543,8 @@ class ExecuteTasksFileSystemCallbackDispatcher
         source_url_(source_url),
         extension_(extension),
         task_id_(task_id),
-        origin_file_urls_(file_urls) {
+        origin_file_urls_(file_urls),
+        local_file_util_(NULL) {
     DCHECK(function_);
   }
 
@@ -652,9 +654,11 @@ class ExecuteTasksFileSystemCallbackDispatcher
     // Check if this file system entry exists first.
     base::PlatformFileInfo file_info;
     FilePath platform_path;
+    if (!local_file_util_.get())

[ericu, 2011/06/17 20:32:07]

Why use lazy initialization?  Can we just set this up at construction time?

Better yet, this should just use the same one as I proposed that the mount point
provider would hold.  We really only need one for the whole system, so creating
and deleting them on every operation is unnecessary.

[Dai Mikurube (NOT FULLTIME), 2011/06/23 08:13:32]

Agreed.  Changed to use external_provider's GetFileSystemFileUtil.

+      local_file_util_.reset(new fileapi::LocalFileSystemFileUtil(
+          fileapi::QuotaFileUtil::GetInstance()));
     fileapi::FileSystemOperationContext file_system_operation_context(
-        profile_->GetFileSystemContext(),
-        fileapi::LocalFileSystemFileUtil::GetInstance());
+        profile_->GetFileSystemContext(), local_file_util_.get());
     if (base::PLATFORM_FILE_OK !=
             fileapi::FileSystemFileUtil::GetInstance()->GetFileInfo(
                 &file_system_operation_context, final_file_path, &file_info,
@@ -724,6 +728,7 @@ class ExecuteTasksFileSystemCallbackDispatcher
   scoped_refptr<const Extension> extension_;
   std::string task_id_;
   std::vector<GURL> origin_file_urls_;
+  scoped_ptr<fileapi::LocalFileSystemFileUtil> local_file_util_;
   DISALLOW_COPY_AND_ASSIGN(ExecuteTasksFileSystemCallbackDispatcher);
 };