[Console] minor fix

Author: nicolas-grekas

Helper/QuestionHelper.php

@@ -309,7 +309,7 @@ private function autocomplete(OutputInterface $output, Question $question, $inpu
                         $remainingCharacters = substr($ret, \strlen(trim($this->mostRecentlyEnteredValue($fullChoice))));
                         $output->write($remainingCharacters);
                         $fullChoice .= $remainingCharacters;
-                        $i = self::strlen($fullChoice);
+                        $i = (false === $encoding = mb_detect_encoding($fullChoice, null, true)) ? \strlen($fullChoice) : mb_strlen($fullChoice, $encoding);
 
                         $matches = array_filter(
                             $autocomplete($ret),

Style/SymfonyStyle.php

@@ -496,8 +496,6 @@ private function createBlock(iterable $messages, string $type = null, string $st
             }
 
             $line = $prefix.$line;
-            $decorationLength = Helper::strlen($line) - Helper::strlenWithoutDecoration($this->getFormatter(), $line);
-            $messageLineLength = min($this->lineLength - $prefixLength - $indentLength + $decorationLength, $this->lineLength);
             $line .= str_repeat(' ', max($this->lineLength - Helper::strlenWithoutDecoration($this->getFormatter(), $line), 0));
 
             if ($style) {