[FileSystem] Add another copy-or-move validation hook for post-write.

webkit/browser/fileapi/copy_or_move_file_validator.h

Index: webkit/browser/fileapi/copy_or_move_file_validator.h
diff --git a/webkit/browser/fileapi/copy_or_move_file_validator.h b/webkit/browser/fileapi/copy_or_move_file_validator.h
index 9b32f5b8d3b101f81caae0d29038d76fb6ebd289..e489da6e61aab7666d1281bb6354eaaa41d7094b 100644
--- a/webkit/browser/fileapi/copy_or_move_file_validator.h
+++ b/webkit/browser/fileapi/copy_or_move_file_validator.h
@@ -25,7 +25,15 @@ class WEBKIT_STORAGE_BROWSER_EXPORT CopyOrMoveFileValidator {
 
   virtual ~CopyOrMoveFileValidator() {}
 
+  // Called on a source file before copying or moving to the final
+  // destination.
   virtual void StartValidation(const ResultCallback& result_callback) = 0;
+
+  // Called on a destination file after copying or moving to the final
+  // destination. Suitable for running AV checks.
+  virtual void StartPostWriteValidation(
+      const base::FilePath& dest_platform_path,
+      const ResultCallback& result_callback) = 0;
 };
 
 class CopyOrMoveFileValidatorFactory {