Fail tests fast if overriding the Windows registry fails.

base/test/test_reg_util_win.h

Index: base/test/test_reg_util_win.h
diff --git a/base/test/test_reg_util_win.h b/base/test/test_reg_util_win.h
index 33bcd216a673be0985d4ccf0f33934e84edb003d..d74028afc4f3ac819cd5347f20879978d94fc8e0 100644
--- a/base/test/test_reg_util_win.h
+++ b/base/test/test_reg_util_win.h
@@ -39,6 +39,8 @@ class RegistryOverrideManager {
   // Multiple overrides to the same hive are not supported and lead to undefined
   // behavior.
   // Optional return of the registry override path.
+  // Calls to these functions must be wrapped in ASSERT_NO_FATAL_FAILURE to
+  // ensure that tests do not proceeed in case of failure to override.
   void OverrideRegistry(HKEY override);
   void OverrideRegistry(HKEY override, base::string16* override_path);
 
@@ -53,7 +55,7 @@ class RegistryOverrideManager {
 
    private:
     HKEY override_;
-    base::win::RegKey temp_key_;
+    base::string16 key_path_;
 
     DISALLOW_COPY_AND_ASSIGN(ScopedRegistryKeyOverride);
   };