Revert of Fix a race condition in ~RegistryHashStoreContentsWin

services/preferences/tracked/registry_hash_store_contents_win.h

Index: services/preferences/tracked/registry_hash_store_contents_win.h
diff --git a/services/preferences/tracked/registry_hash_store_contents_win.h b/services/preferences/tracked/registry_hash_store_contents_win.h
index dd55669815790eabf4ab017c4e4b5f1280726c3d..0b3b396205d60cda624442ace27e58a48357ce79 100644
--- a/services/preferences/tracked/registry_hash_store_contents_win.h
+++ b/services/preferences/tracked/registry_hash_store_contents_win.h
@@ -8,29 +8,18 @@
 #include "base/macros.h"
 #include "base/strings/string16.h"
 #include "services/preferences/tracked/hash_store_contents.h"
-#include "services/preferences/tracked/temp_scoped_dir_cleaner.h"
-
-// Helper object to clear registry entries for scoped temporary pref stores.
-class TempScopedDirRegistryCleaner : public TempScopedDirCleaner {
- public:
-  void SetRegistryPath(const base::string16& registry_path);
-
- private:
-  friend class base::RefCountedThreadSafe<TempScopedDirRegistryCleaner>;
-  ~TempScopedDirRegistryCleaner() override;
-
-  base::string16 registry_path_;
-};
 
 // Implements HashStoreContents by storing MACs in the Windows registry.
 class RegistryHashStoreContentsWin : public HashStoreContents {
  public:
   // Constructs a RegistryHashStoreContents which acts on a registry entry
-  // defined by |registry_path| and |store_key|.
-  explicit RegistryHashStoreContentsWin(
-      const base::string16& registry_path,
-      const base::string16& store_key,
-      scoped_refptr<TempScopedDirCleaner> temp_dir_cleaner);
+  // defined by |registry_path| and |store_key|. If |store_key| begins with
+  // base::ScopedTempDir::GetTempDirPrefix(), this RegistryHashStoreContentsWin
+  // will self Reset() on destruction to avoid proliferating keys in tests that
+  // create a profile in a ScopedTempDir (https://crbug.com/721245).
+  explicit RegistryHashStoreContentsWin(const base::string16& registry_path,
+                                        const base::string16& store_key);
+
   ~RegistryHashStoreContentsWin() override;
 
   // HashStoreContents overrides:
@@ -60,7 +49,7 @@
       const RegistryHashStoreContentsWin& other);
 
   const base::string16 preference_key_name_;
-  scoped_refptr<TempScopedDirCleaner> temp_dir_cleaner_;
+  const bool reset_on_delete_;
 };
 
 #endif  // SERVICES_PREFERENCES_TRACKED_REGISTRY_HASH_STORE_CONTENTS_WIN_H_