Wired GDataFileSystem::GetFile() method with internal cache.

chrome/browser/chromeos/gdata/gdata_operations.h

Index: chrome/browser/chromeos/gdata/gdata_operations.h
diff --git a/chrome/browser/chromeos/gdata/gdata_operations.h b/chrome/browser/chromeos/gdata/gdata_operations.h
index 0843ea0953aaef76b54fc3865d61737a18d3e0ab..bb6d74b3fbaeb95e004a82136a491f2241e9cdf6 100644
--- a/chrome/browser/chromeos/gdata/gdata_operations.h
+++ b/chrome/browser/chromeos/gdata/gdata_operations.h
@@ -138,6 +138,7 @@ class UrlFetchOperationBase : public GDataOperationInterface,
   scoped_refptr<base::MessageLoopProxy> relay_proxy_;
   int re_authenticate_count_;
   bool save_temp_file_;
+  FilePath output_file_path_;
   scoped_ptr<content::URLFetcher> url_fetcher_;
 };
 
@@ -244,7 +245,8 @@ class DownloadFileOperation : public UrlFetchOperationBase {
                         Profile* profile,
                         const DownloadActionCallback& callback,
                         const GURL& document_url,
-                        const FilePath& virtual_path);
+                        const FilePath& virtual_path,
+                        const FilePath& output_file_path);
   virtual ~DownloadFileOperation();
 
  protected: