Revert of Add best-effort/allow rollback flags on WorkItem.

chrome/installer/util/self_reg_work_item.cc

Index: chrome/installer/util/self_reg_work_item.cc
diff --git a/chrome/installer/util/self_reg_work_item.cc b/chrome/installer/util/self_reg_work_item.cc
index dc7e722110626da20a0dae93b3d58ec5c1062cae..7157d6e4ae0935aeda063f4f17164bd329b0cd2d 100644
--- a/chrome/installer/util/self_reg_work_item.cc
+++ b/chrome/installer/util/self_reg_work_item.cc
@@ -90,10 +90,15 @@
   return success;
 }
 
-bool SelfRegWorkItem::DoImpl() {
-  return RegisterDll(do_register_);
+bool SelfRegWorkItem::Do() {
+  bool success = RegisterDll(do_register_);
+  if (ignore_failure_)
+    success = true;
+  return success;
 }
 
-void SelfRegWorkItem::RollbackImpl() {
-  RegisterDll(!do_register_);
+void SelfRegWorkItem::Rollback() {
+  if (!ignore_failure_) {
+    RegisterDll(!do_register_);
+  }
 }