Added Protector, hooked up DSE verification with error bubble.

chrome/browser/protector/setting_change.h

Index: chrome/browser/protector/setting_change.h
diff --git a/chrome/browser/protector/setting_change.h b/chrome/browser/protector/setting_change.h
new file mode 100644
index 0000000000000000000000000000000000000000..0a1e1d2910bebd3e7117d16202c40548da56be73
--- /dev/null
+++ b/chrome/browser/protector/setting_change.h
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+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_PROTECTOR_SETTING_CHANGE_H_
+#define CHROME_BROWSER_PROTECTOR_SETTING_CHANGE_H_
+#pragma once
+
+#include <string>
+#include <vector>
+
+#include "base/basictypes.h"
+#include "base/string16.h"
+
+class TemplateURL;
+
+namespace protector {
+
+class Protector;
+
+// Base class for setting change tracked by Protector.
+class SettingChange {
+ public:
+  // IDs of changes Protector currently tracks.
+  enum Type {
+    // Default search engine has been changed.
+    kSearchEngineChanged,
+
+    // Home page has been changed.
+    kHomePageChanged,
+  };
+
+  explicit SettingChange(Type type) : type_(type) {}
+  virtual ~SettingChange() {}
+
+  Type type() const { return type_; }
+
+  // Returns the old setting presentation to be shown to user.
+  // Returns empty string if the old setting is unavailable.
+  virtual string16 GetOldSetting() const = 0;
+
+  // Returns the new setting presentation to be shown to user.
+  virtual string16 GetNewSetting() const = 0;
+
+  // Persists new setting if needed.
+  virtual void Accept(Protector* protector) {}
+
+  // Restores old setting value if needed.
+  virtual void Revert(Protector* protector) {}
+
+  // Called when user ignored the change.
+  virtual void DoDefault(Protector* protector) {}
+
+ private:
+  // Type of the change. Used for strings lookup by UI.
+  // TODO(avayvod): Refactor string selection logic via polymorphism.
+  Type type_;
+
+  DISALLOW_COPY_AND_ASSIGN(SettingChange);
+};
+
+typedef std::vector<SettingChange*> SettingChangeVector;
+typedef void (SettingChange::*SettingChangeAction)(Protector*);
+
+// Allocates and initializes SettingChange implementation for default search
+// provider setting.
+SettingChange* CreateDefaultSearchProviderChange(
+    const TemplateURL* actual,
+    const TemplateURL* backup);
+
+}  // namespace protector
+
+#endif  // CHROME_BROWSER_PROTECTOR_SETTING_CHANGE_H_