Remove dangerous std::string constructor for der::Input

net/der/input.h

 // Copyright 2015 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 NET_DER_INPUT_H_
 #define NET_DER_INPUT_H_
 
 #include <stdint.h>
 #include <string>
 
@@ skipping 31 matching lines @@
   Input();
 
   // Creates an Input from a constant array |data|.
   template <size_t N>
   explicit Input(const uint8_t(&data)[N])
       : data_(data), len_(N) {}
 
   // Creates an Input from the given |data| and |len|.
   Input(const uint8_t* data, size_t len);
 
-  // Creates an Input from the given string |s|.
-  explicit Input(const std::string& s);
-
   // Returns the length in bytes of an Input's data.
   size_t Length() const { return len_; }
 
   // Return true if the Input's data and |other|'s data are byte-wise equal.
   bool Equals(const Input& other) const;
 
   // Returns a pointer to the Input's data. This method is marked as "unsafe"
   // because access to the Input's data should be done through ByteReader
   // instead. This method should only be used where using a ByteReader truly
   // is not an option.
@@ skipping 86 matching lines @@
   explicit Mark(const uint8_t* ptr);
   Mark();
   const uint8_t* ptr_;
 };
 
 }  // namespace der
 
 }  // namespace net
 
 #endif  // NET_DER_INPUT_H_