Add GetURLForBrowserTab method to the external file system backend.

chrome/browser/chromeos/fileapi/file_system_backend_delegate.h

Index: chrome/browser/chromeos/fileapi/file_system_backend_delegate.h
diff --git a/chrome/browser/chromeos/fileapi/file_system_backend_delegate.h b/chrome/browser/chromeos/fileapi/file_system_backend_delegate.h
index b11c86a5ddefea8b979f70f08bffa79c3e15430d..0c56149eb0f611f405145dc26c11ccc820e326ef 100644
--- a/chrome/browser/chromeos/fileapi/file_system_backend_delegate.h
+++ b/chrome/browser/chromeos/fileapi/file_system_backend_delegate.h
@@ -6,9 +6,13 @@
 #define CHROME_BROWSER_CHROMEOS_FILEAPI_FILE_SYSTEM_BACKEND_DELEGATE_H_
 
 #include "base/basictypes.h"
+#include "base/callback_forward.h"
 #include "base/memory/scoped_ptr.h"
+#include "webkit/browser/fileapi/file_system_backend.h"
 #include "webkit/common/fileapi/file_system_types.h"
 
+class GURL;
+
 namespace base {
 class Time;
 }  // namespace base
@@ -22,10 +26,6 @@ class FileStreamWriter;
 class WatcherManager;
 }  // namespace storage
 
-namespace storage {
-class FileStreamReader;
-}  // namespace storage
-
 namespace chromeos {
 
 // This is delegate interface to inject the implementation of the some methods
@@ -55,6 +55,13 @@ class FileSystemBackendDelegate {
   // stay valid until shutdown.
   virtual storage::WatcherManager* GetWatcherManager(
       const storage::FileSystemURL& url) = 0;
+
+  // Called from FileSystemBackend::GetRedirectURLForContents.  Please ensure
+  // that the returned URL is secure to be opened in a browser tab, or referred
+  // from <img>, <video>, XMLHttpRequest, etc...
+  virtual void GetRedirectURLForContents(
+      const storage::FileSystemURL& url,
+      const storage::URLCallback& callback) = 0;
 };
 
 }  // namespace chromeos