Enable "Hide Extension" option when "Save Link As" on the Mac

chrome/browser/download/download_target_determiner.h

Index: chrome/browser/download/download_target_determiner.h
diff --git a/chrome/browser/download/download_target_determiner.h b/chrome/browser/download/download_target_determiner.h
index 0bb4cb034e297f6e0540ce9aee9d75502a64efe0..5bae7b9f7c6ffb80de0f841a0948854f38612a45 100644
--- a/chrome/browser/download/download_target_determiner.h
+++ b/chrome/browser/download/download_target_determiner.h
@@ -184,7 +184,8 @@ class DownloadTargetDeterminer
 
   // Callback invoked after the file picker completes. Cancels the download if
   // the user cancels the file picker.
-  void PromptUserForDownloadPathDone(const base::FilePath& virtual_path);
+  void PromptUserForDownloadPathDone(const base::FilePath& virtual_path,
+                                     bool hide_file_extension);
 
   // Up until this point, the path that was used is considered to be a virtual
   // path. This step determines the local file system path corresponding to this
@@ -310,6 +311,7 @@ class DownloadTargetDeterminer
   base::FilePath intermediate_path_;
   std::string mime_type_;
   bool is_filetype_handled_safely_;
+  bool hide_file_extension_;
 
   content::DownloadItem* download_;
   const bool is_resumption_;