[presubmit] Enable readability/namespace linter checking.

src/ast-value-factory.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 31 matching lines @@
       literal_bytes_(lb), pos_(0) {}
 
   bool HasMore() { return pos_ < literal_bytes_.length(); }
   uint16_t GetNext() { return literal_bytes_[pos_++]; }
 
  private:
   Vector<const byte> literal_bytes_;
   int pos_;
 };
 
-}
+}  // namespace
 
 class AstRawStringInternalizationKey : public HashTableKey {
  public:
   explicit AstRawStringInternalizationKey(const AstRawString* string)
       : string_(string) {}
 
   bool IsMatch(Object* other) override {
     if (string_->is_one_byte_)
       return String::cast(other)->IsOneByteEqualTo(string_->literal_bytes_);
     return String::cast(other)->IsTwoByteEqualTo(
@@ skipping 317 matching lines @@
   const AstRawString* lhs = static_cast<AstRawString*>(a);
   const AstRawString* rhs = static_cast<AstRawString*>(b);
   if (lhs->is_one_byte() != rhs->is_one_byte()) return false;
   if (lhs->hash() != rhs->hash()) return false;
   int len = lhs->byte_length();
   if (rhs->byte_length() != len) return false;
   return memcmp(lhs->raw_data(), rhs->raw_data(), len) == 0;
 }
 }  // namespace internal
 }  // namespace v8