AK: Fix JSON parser crashing when encountering UTF-8

The mechanism that caches the most recently seen string for each first
character was indexing into the cache using a 'char' subscript. Oops!

1 files changed, 1 insertions, 1 deletions

diff --git a/AK/JsonParser.cpp b/AK/JsonParser.cpp
index 774def6e4c..5c634f27de 100644
--- a/AK/JsonParser.cpp
+++ b/AK/JsonParser.cpp
@@ -103,7 +103,7 @@ String JsonParser::consume_quoted_string()
     if (buffer.is_empty())
         return String::empty();
 
-    auto& last_string_starting_with_character = m_last_string_starting_with_character[(int)buffer.first()];
+    auto& last_string_starting_with_character = m_last_string_starting_with_character[(u8)buffer.first()];
     if (last_string_starting_with_character.length() == (size_t)buffer.size()) {
         if (!memcmp(last_string_starting_with_character.characters(), buffer.data(), buffer.size()))
             return last_string_starting_with_character;