Revert of Add PrefStore::GetValues

components/prefs/pref_store.h

Index: components/prefs/pref_store.h
diff --git a/components/prefs/pref_store.h b/components/prefs/pref_store.h
index 7964f1f0093936b1860162dd26622130513b0637..ef2bc494d150b8d2366a72f1dfd36f282e553687 100644
--- a/components/prefs/pref_store.h
+++ b/components/prefs/pref_store.h
@@ -5,7 +5,6 @@
 #ifndef COMPONENTS_PREFS_PREF_STORE_H_
 #define COMPONENTS_PREFS_PREF_STORE_H_
 
-#include <memory>
 #include <string>
 
 #include "base/macros.h"
@@ -13,7 +12,6 @@
 #include "components/prefs/base_prefs_export.h"
 
 namespace base {
-class DictionaryValue;
 class Value;
 }
 
@@ -54,9 +52,6 @@
   virtual bool GetValue(const std::string& key,
                         const base::Value** result) const = 0;
 
-  // Get all the values. Never returns a null pointer.
-  virtual std::unique_ptr<base::DictionaryValue> GetValues() const = 0;
-
  protected:
   friend class base::RefCounted<PrefStore>;
   virtual ~PrefStore() {}