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

chrome/installer/util/work_item.h

Index: chrome/installer/util/work_item.h
diff --git a/chrome/installer/util/work_item.h b/chrome/installer/util/work_item.h
index e28bedfa2c425721cb5d9eb5f75e63586e35b23a..446b4914ff51d541fedce318597a844a388731d1 100644
--- a/chrome/installer/util/work_item.h
+++ b/chrome/installer/util/work_item.h
@@ -35,22 +35,6 @@
 
 // A base class that defines APIs to perform/rollback an action or a
 // sequence of actions during install/update/uninstall.
-//
-// Subclasses must implement DoImpl() and RollbackImpl().
-//
-// Do() calls DoImpl(). When the "best-effort" flag is true, it always returns
-// true. Otherwise, it returns the value returned by DoImpl(). Implementations
-// of DoImpl() may use the "best-effort" flag as an indication that they should
-// do as much work as possible (i.e., shouldn't abort as soon as one of the
-// actions they have to perform fails). By default, the "best-effort" flag is
-// false.
-//
-// Rollback() calls RollbackImpl() when the "rollback enabled" flag is true.
-// Otherwise, it's a no-op. Implementations of DoImpl() may read the "rollback
-// enabled" flag to determine whether they should save state to support
-// rollback. By default, the "rollback enabled" flag is true.
-//
-// The "best-effort" and "rollback enabled" must be set before Do() is invoked.
 class WorkItem {
  public:
   // A callback that returns the desired value based on the |existing_value|.
@@ -135,10 +119,12 @@
       const std::wstring& value_name);
 
   // Create a DeleteTreeWorkItem that recursively deletes a file system
-  // hierarchy at the given root path.
+  // hierarchy at the given root path. A key file can be optionally specified
+  // by key_path.
   static DeleteTreeWorkItem* CreateDeleteTreeWorkItem(
       const base::FilePath& root_path,
-      const base::FilePath& temp_path);
+      const base::FilePath& temp_path,
+      const std::vector<base::FilePath>& key_paths);
 
   // Create a MoveTreeWorkItem that recursively moves a file system hierarchy
   // from source path to destination path.
@@ -198,24 +184,38 @@
   // a list of WorkItems.
   static WorkItemList* CreateWorkItemList();
 
+  // Create an empty WorkItemList that cannot be rolled back.
+  // Such a work item list executes all items on a best effort basis and does
+  // not abort execution if an item in the list fails.
+  static WorkItemList* CreateNoRollbackWorkItemList();
+
   // Create a conditional work item list that will execute only if
   // condition->ShouldRun() returns true. The WorkItemList instance
   // assumes ownership of condition.
   static WorkItemList* CreateConditionalWorkItemList(Condition* condition);
 
-  // Perform the actions of WorkItem. Returns true if success or if
-  // best_effort(). Can only be called once per instance.
-  bool Do();
-
-  // Rollback any actions previously carried out by this WorkItem if
-  // rollback_enabled(). Can only be called once per instance, after Do() has
-  // returned.
-  void Rollback();
-
-  void set_best_effort(bool best_effort);
-  bool best_effort() const { return best_effort_; }
-  void set_rollback_enabled(bool rollback_enabled);
-  bool rollback_enabled() const { return rollback_enabled_; }
+  // Perform the actions of WorkItem. Returns true if success, returns false
+  // otherwise.
+  // If the WorkItem is transactional, then Do() is done as a transaction.
+  // If it returns false, there will be no change on the system.
+  virtual bool Do() = 0;
+
+  // Rollback any actions previously carried out by this WorkItem. If the
+  // WorkItem is transactional, then the previous actions can be fully
+  // rolled back. If the WorkItem is non-transactional, the rollback is a
+  // best effort.
+  virtual void Rollback() = 0;
+
+  // If called with true, this WorkItem may return true from its Do() method
+  // even on failure and Rollback will have no effect.
+  void set_ignore_failure(bool ignore_failure) {
+    ignore_failure_ = ignore_failure;
+  }
+
+  // Returns true if this WorkItem should ignore failures.
+  bool ignore_failure() const {
+    return ignore_failure_;
+  }
 
   // Sets an optional log message that a work item may use to print additional
   // instance-specific information.
@@ -227,30 +227,13 @@
   const std::string& log_message() const { return log_message_; }
 
  protected:
-  enum State {
-    BEFORE_DO,
-    AFTER_DO,
-    AFTER_ROLLBACK,
-  };
-
   WorkItem();
 
-  State state() const { return state_; }
+  // Specifies whether this work item my fail to complete and yet still
+  // return true from Do().
+  bool ignore_failure_;
 
   std::string log_message_;
-
- private:
-  // Called by Do(). Performs the actions of the Workitem.
-  virtual bool DoImpl() = 0;
-
-  // Called by Rollback() if rollback_enabled() is true. Rollbacks the actions
-  // performed by DoImpl(). Implementations must support invocation of this even
-  // when DoImpl() returned false.
-  virtual void RollbackImpl() = 0;
-
-  State state_ = BEFORE_DO;
-  bool best_effort_ = false;
-  bool rollback_enabled_ = true;
 };
 
 #endif  // CHROME_INSTALLER_UTIL_WORK_ITEM_H_