Remove PrefServiceSimple, replacing it with PrefService and PrefRegistrySimple.

chrome/test/base/testing_pref_service.h

Index: chrome/test/base/testing_pref_service.h
diff --git a/chrome/test/base/testing_pref_service.h b/chrome/test/base/testing_pref_service.h
index 5c921bfd4319e5a8a840569fb78b708486ecd62f..94b1b5a55d2df4f8adb1d5038afc95d2b3aa56d8 100644
--- a/chrome/test/base/testing_pref_service.h
+++ b/chrome/test/base/testing_pref_service.h
@@ -7,6 +7,7 @@
 
 #include "base/memory/ref_counted.h"
 #include "base/prefs/testing_pref_store.h"
+#include "chrome/browser/prefs/pref_registrar_simple.h"
 #include "chrome/browser/prefs/pref_service.h"
 
 class DefaultPrefStore;
@@ -75,14 +76,18 @@ class TestingPrefServiceBase : public SuperPrefService {
   DISALLOW_COPY_AND_ASSIGN(TestingPrefServiceBase);
 };
 
-// Test version of PrefServiceSimple.
+// Test version of PrefService.
 class TestingPrefServiceSimple
-    : public TestingPrefServiceBase<PrefServiceSimple> {
+    : public TestingPrefServiceBase<PrefService> {
  public:
   TestingPrefServiceSimple();
   virtual ~TestingPrefServiceSimple();
 
+  PrefRegistrarSimple* registrar() { return &registrar_; }
+
  private:
+  PrefRegistrarSimple registrar_;
+
   DISALLOW_COPY_AND_ASSIGN(TestingPrefServiceSimple);
 };
 
@@ -116,7 +121,7 @@ class ScopedTestingLocalState {
 };
 
 template<>
-TestingPrefServiceBase<PrefServiceSimple>::TestingPrefServiceBase(
+TestingPrefServiceBase<PrefService>::TestingPrefServiceBase(
     TestingPrefStore* managed_prefs,
     TestingPrefStore* user_prefs,
     TestingPrefStore* recommended_prefs,