Delete base/prefs and update callers to use components.

components/prefs/pref_registry_simple.h

Index: components/prefs/pref_registry_simple.h
diff --git a/components/prefs/pref_registry_simple.h b/components/prefs/pref_registry_simple.h
index 4348029642fc4bb9ad099e340ba0adf158740d91..e326787159031ad3ba7cfca3c320526bd7599d9f 100644
--- a/components/prefs/pref_registry_simple.h
+++ b/components/prefs/pref_registry_simple.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef BASE_PREFS_PREF_REGISTRY_SIMPLE_H_
-#define BASE_PREFS_PREF_REGISTRY_SIMPLE_H_
+#ifndef COMPONENTS_PREFS_PREF_REGISTRY_SIMPLE_H_
+#define COMPONENTS_PREFS_PREF_REGISTRY_SIMPLE_H_
 
 #include <stdint.h>
 
@@ -20,7 +20,7 @@ class ListValue;
 }
 
 // A simple implementation of PrefRegistry.
-class BASE_PREFS_EXPORT PrefRegistrySimple : public PrefRegistry {
+class COMPONENTS_PREFS_EXPORT PrefRegistrySimple : public PrefRegistry {
  public:
   PrefRegistrySimple();
 
@@ -88,4 +88,4 @@ class BASE_PREFS_EXPORT PrefRegistrySimple : public PrefRegistry {
   DISALLOW_COPY_AND_ASSIGN(PrefRegistrySimple);
 };
 
-#endif  // BASE_PREFS_PREF_REGISTRY_SIMPLE_H_
+#endif  // COMPONENTS_PREFS_PREF_REGISTRY_SIMPLE_H_