Add rollback support to DeleteRegKeyWorkItem....

chrome/installer/util/delete_reg_key_work_item.h

Index: chrome/installer/util/delete_reg_key_work_item.h
===================================================================
--- chrome/installer/util/delete_reg_key_work_item.h	(revision 76372)
+++ chrome/installer/util/delete_reg_key_work_item.h	(working copy)
@@ -11,9 +11,14 @@
 #include <string>
 
 #include "base/basictypes.h"
+#include "base/scoped_ptr.h"
 #include "chrome/installer/util/work_item.h"
 
-// A WorkItem subclass that deletes a registry key at the given path.
+// A WorkItem subclass that deletes a registry key at the given path.  Be aware
+// that if failures are not ignored, an in-memory backup is made of the key and
+// its values.  In the event of rollback, the key's values and subkeys are
+// restored, but the key and its subkeys take on their default security
+// descriptors.

[robertshield, 2011/03/01 16:04:43]

Could simplify the above comment to read:

"Be aware that in the event of rollback the key's values and subkeys are
restored but the key and its subkeys take on their default security
descriptors."

since if failures ARE ignored, then rollback isn't going to happen.

[grt (UTC plus 2), 2011/03/01 20:54:02]

Done.

 class DeleteRegKeyWorkItem : public WorkItem {
  public:
   virtual ~DeleteRegKeyWorkItem();
@@ -23,6 +28,7 @@
   virtual void Rollback();
 
  private:
+  class RegKeyBackup;
   friend class WorkItem;
 
   DeleteRegKeyWorkItem(HKEY predefined_root, const std::wstring& path);
@@ -34,10 +40,9 @@
   // Path of the key to be deleted.
   std::wstring path_;
 
-  // Path in the registry that the key is backed up to.
-  std::wstring backup_path_;
+  // Backup of the deleted key.
+  scoped_ptr<RegKeyBackup> backup_;
 
- private:
   DISALLOW_COPY_AND_ASSIGN(DeleteRegKeyWorkItem);
 };