Fixed file/directory url resolution for external mount point provider.

webkit/fileapi/file_system_file_util_proxy.h

Index: webkit/fileapi/file_system_file_util_proxy.h
===================================================================
--- webkit/fileapi/file_system_file_util_proxy.h	(revision 82028)
+++ webkit/fileapi/file_system_file_util_proxy.h	(working copy)
@@ -40,6 +40,9 @@
                     const PlatformFileInfo& /* file_info */,
                     const FilePath& /* platform_path, where possible */
                     >::Type GetFileInfoCallback;
+  typedef Callback2<PlatformFileError /* error code */,
+                    const FilePath& /* local_path, where possible */
+                    >::Type GetLocalPathCallback;
   typedef base::FileUtilProxy::ReadDirectoryCallback ReadDirectoryCallback;
 
   // Creates or opens a file with the given flags.  It is invalid to pass NULL
@@ -74,6 +77,13 @@
       const FilePath& file_path,
       EnsureFileExistsCallback* callback);
 
+  // Maps virtual file patch to its local physical location.
+  static bool GetLocalPath(
+      const FileSystemOperationContext& context,
+      scoped_refptr<MessageLoopProxy> message_loop_proxy,
+      const FilePath& virtual_path,
+      GetLocalPathCallback* callback);
+
   // Retrieves the information about a file. It is invalid to pass NULL for the
   // callback.
   static bool GetFileInfo(