Revert of Move base/prefs to components/prefs

base/prefs/mock_pref_change_callback.h

Index: base/prefs/mock_pref_change_callback.h
diff --git a/base/prefs/mock_pref_change_callback.h b/base/prefs/mock_pref_change_callback.h
index 90ad29472e30ee6c7281910d1010dc83e221d404..3030fab17c23c9ed6775e70eee65b45ea6d5295f 100644
--- a/base/prefs/mock_pref_change_callback.h
+++ b/base/prefs/mock_pref_change_callback.h
@@ -2,6 +2,50 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// TODO(brettw) remove this forwarding header when prefs is completely moved to
-// components.
-#include "components/prefs/mock_pref_change_callback.h"
+#ifndef BASE_PREFS_MOCK_PREF_CHANGE_CALLBACK_H_
+#define BASE_PREFS_MOCK_PREF_CHANGE_CALLBACK_H_
+
+#include <string>
+
+#include "base/prefs/pref_change_registrar.h"
+#include "base/prefs/pref_service.h"
+#include "testing/gmock/include/gmock/gmock.h"
+
+using testing::Pointee;
+using testing::Property;
+using testing::Truly;
+
+// Matcher that checks whether the current value of the preference named
+// |pref_name| in |prefs| matches |value|. If |value| is NULL, the matcher
+// checks that the value is not set.
+MATCHER_P3(PrefValueMatches, prefs, pref_name, value, "") {
+  const PrefService::Preference* pref = prefs->FindPreference(pref_name);
+  if (!pref)
+    return false;
+
+  const base::Value* actual_value = pref->GetValue();
+  if (!actual_value)
+    return value == NULL;
+  if (!value)
+    return actual_value == NULL;
+  return value->Equals(actual_value);
+}
+
+// A mock for testing preference notifications and easy setup of expectations.
+class MockPrefChangeCallback {
+ public:
+  explicit MockPrefChangeCallback(PrefService* prefs);
+  virtual ~MockPrefChangeCallback();
+
+  PrefChangeRegistrar::NamedChangeCallback GetCallback();
+
+  MOCK_METHOD1(OnPreferenceChanged, void(const std::string&));
+
+  void Expect(const std::string& pref_name,
+              const base::Value* value);
+
+ private:
+  PrefService* prefs_;
+};
+
+#endif  // BASE_PREFS_MOCK_PREF_CHANGE_CALLBACK_H_