Mac: Make it easier for views to correctly draw with a theme.

chrome/browser/ui/cocoa/download/download_item_button.h

Index: chrome/browser/ui/cocoa/download/download_item_button.h
diff --git a/chrome/browser/ui/cocoa/download/download_item_button.h b/chrome/browser/ui/cocoa/download/download_item_button.h
index ecc2ee3f87d0e3cb8234f83051b5920655d0586d..e0124913885ae0ec4c59bfeb553794865cb4823d 100644
--- a/chrome/browser/ui/cocoa/download/download_item_button.h
+++ b/chrome/browser/ui/cocoa/download/download_item_button.h
@@ -6,12 +6,14 @@
 
 #include "base/files/file_path.h"
 #import "chrome/browser/ui/cocoa/draggable_button.h"
+#import "chrome/browser/ui/cocoa/themed_window.h"
 
 @class DownloadItemController;
 
 // A button that is a drag source for a file and that displays a context menu
 // instead of firing an action when clicked in a certain area.
-@interface DownloadItemButton : DraggableButton<NSMenuDelegate> {
+@interface DownloadItemButton
+    : DraggableButton<NSMenuDelegate, ThemedWindowDrawing> {
  @private
   base::FilePath downloadPath_;
   DownloadItemController* controller_;  // weak