Revert of Delete base/prefs and update callers to use components.

components/prefs/writeable_pref_store.h

 // Copyright 2014 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 COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_
-#define COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_
+#ifndef BASE_PREFS_WRITEABLE_PREF_STORE_H_
+#define BASE_PREFS_WRITEABLE_PREF_STORE_H_
 
 #include <stdint.h>
 
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
 #include "components/prefs/pref_store.h"
 
 namespace base {
 class Value;
 }
 
 // A pref store that can be written to as well as read from.
-class COMPONENTS_PREFS_EXPORT WriteablePrefStore : public PrefStore {
+class BASE_PREFS_EXPORT WriteablePrefStore : public PrefStore {
  public:
   // PrefWriteFlags can be used to change the way a pref will be written to
   // storage.
   enum PrefWriteFlags : uint32_t {
     // No flags are specified.
     DEFAULT_PREF_WRITE_FLAGS = 0,
 
     // This marks the pref as "lossy". There is no strict time guarantee on when
     // a lossy pref will be persisted to permanent storage when it is modified.
     LOSSY_PREF_WRITE_FLAG = 1 << 1
@@ skipping 30 matching lines @@
                                 scoped_ptr<base::Value> value,
                                 uint32_t flags) = 0;
 
  protected:
   ~WriteablePrefStore() override {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(WriteablePrefStore);
 };
 
-#endif  // COMPONENTS_PREFS_WRITEABLE_PREF_STORE_H_
+#endif  // BASE_PREFS_WRITEABLE_PREF_STORE_H_