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

net/der/input.h

Index: net/der/input.h
diff --git a/net/der/input.h b/net/der/input.h
index 6731b0c0600afd22f623141252b7e2b58d413061..f8eb467a482dc765788c720da9e4ec6b9102522d 100644
--- a/net/der/input.h
+++ b/net/der/input.h
@@ -49,9 +49,6 @@ class NET_EXPORT_PRIVATE Input {
   // 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_; }