AK+Everywhere: Disallow Error::from_string_view(FooString)

That pattern seems to show up a lot in code written by people that
aren't intimately familiar with the lifetime model of Error and Strings.
This commit makes the compiler detect it and present a more helpful
diagnostic than "garbage string at runtime".

Userland/Libraries/LibWasm/AbstractMachine/Validator.h

@@ -33,7 +33,7 @@ struct Context {
 
 struct ValidationError : public Error {
     ValidationError(DeprecatedString error)
-        : Error(Error::from_string_view(error))
+        : Error(Error::from_string_view(error.view()))
         , error_string(move(error))
     {
     }