Remove the Value class names from the global namespace.

base/values.h

Index: base/values.h
diff --git a/base/values.h b/base/values.h
index 65121808e641a1da3b011ba2a919dcaba2662360..8caf8350a8bfc76b00b96044213b55912466031f 100644
--- a/base/values.h
+++ b/base/values.h
@@ -31,11 +31,6 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/strings/string16.h"
 
-// This file declares "using base::Value", etc. at the bottom, so that
-// current code can use these classes without the base namespace. In
-// new code, please always use base::Value, etc. or add your own
-// "using" declaration.
-// http://crbug.com/88666
 namespace base {
 
 class DictionaryValue;
@@ -528,10 +523,4 @@ BASE_EXPORT inline std::ostream& operator<<(std::ostream& out,
 
 }  // namespace base
 
-// http://crbug.com/88666
-using base::DictionaryValue;
-using base::ListValue;
-using base::StringValue;
-using base::Value;
-
 #endif  // BASE_VALUES_H_